2013 of Achievements in Materials
and Manufacturing Engineering of Achievements in Materials and Manufacturing Engineering
Laser surface treatment of cast Al-Si-Cu alloys
K. Labisz*
Institute of Engineering Materials and Biomaterials, Silesian University of Technology, ul. Konarskiego 18a, 44-100 Gliwice, Poland
* Corresponding e-mail address: krzysztof.labisz@polsl.pl Received 29.10.2013; published in revised form 01.12.2013
Manufacturing and processing
AbstrAct
Purpose: The test results presented in this chapter concern formation of the quasi-composite MMCs structure on the surface of elements from aluminium cast alloys AC-AlSi9Cu and AC-AlSi9Cu4 by fusion of the carbide or ceramic particles WC, SiC, ZrO2 and Al2O3 in the surface of alloys. In addition, within the scope of the tests the phase transformations and precipitation processes present during laser remelting and fusion at appropriately selected parameters: laser power, the rate of fusion and quantity of the ceramic powder fed have been partially examined.
Design/methodology/approach: In general, the laser surface processing should result in achievement of the surface layer with the most favourable physical and mechanical properties, in particular enhancement of surface hardness, improvement of abrasion resistance and resistance to corrosion is assumed in relation to the selected aluminium alloys after standard thermal processing.
Findings: The presented results of the surface layer include analysis of the mechanisms responsible for formation of the layer, and particularly concern remelting of the substrate and its crystallisation at various parameters of the High Power Diode Laser (HPDL) and the technological conditions of the surface processing, remelting and fusion of the particles in the surface of cast alloys ACAlSi9Cu and ACAlSi9Cu4. For the purpose of testing the structure of the obtained surface layers the test methods making use of the light microscopy method supported with computer image analysis, transmission and scanning electron microscopy, X-ray analysis, X-ray microanalysis, as well as methods for testing the mechanical and usable properties have been used.
Practical implications: What is more, development of the technology of surface refinement of cast alloys Al-Si-Cu with the laser fusion methods will allow for complex solving of the problem related to enhancement of the surface layer properties, taking into account both economic and ecological aspects.
Originality/value: On the basis of the test result analysis it has been pointed out that in case of the analysed aluminium cast alloys the applied laser surface processing, and the thermal processing preceding it, ensuring occurrence of the mechanisms responsible for material strengthening, enable enhancement of the mechanical and usable properties of the examined alloys. An essential objective is also to indicate the multiple possibilities for continuation of the tests, regarding the light metal alloys aluminium, magnesium and titanium, broadening the current knowledge within the scope of elements and light structures.
Keywords: Laser treatment; Surface treatment; Aluminium alloys; Alloying Reference to this paper should be given in the following way:
K. Labisz, Laser surface treatment of cast Al-Si-Cu alloys, Journal of Achievements in Materials and Manufacturing Engineering 61/2 (2013) 63-86.
1.Introduction
While analysing the given element in terms of its internal structure as well as possible, future working conditions it should be remembered that the product properties depend mainly on two factors: internal structure of the material, from which it has been made and on the condition of the external surface having both direct mechanical and chemical contact with the environment, including inter alia with the tools processing the given element, as well as during exploitation with the surfaces of other co-operating elements. The character of the surface, its morphology and properties often have direct impact on the product manufacturing, and in the most cases the surface quality decides just on its functional qualities. The surface layer of the material is characterised not only by its shape, roughness and appearance (colour, transparency), but also by a number of other properties that are completely different from the properties of the inside of the material, which in a significant manner influence the various types of mechanisms occurring around its area, i.e.: friction, fatigue, corrosion, erosion, diffusion, conductivity and determine the usability and fitness of the surface processed elements for possible uses. Despite the fact that the surface layer of the engineering materials may not be formed independently from the substrate, nevertheless the requirements set to the inside of the product are usually different from the conditions that are expected from the manufactured surfaces. Often due to economic, technological or even practical reasons it is more advantageous to select the substrate in such a way that it would conform to the general resistance assumptions anticipated for the given element, and as a next step to apply one of the techniques for its surface treatment in order to protect it against destruction or to enhance its usable properties. Therefore the material selection constitute such an important stage of design, which is often executed due to destructive processes present during the given work environment.
Attention should also be paid to the fact that formation of the new materials, including also the ones with the applied coating, carries the possibility of discovering the pioneering, previously unidentified structural and wear mechanisms or specification of broader scope of the already existing mechanisms.
In relation to the current market demand for light and reliable constructions, aluminium alloys, belonging to the group of the construction materials, characterised by a number of good mechanical and usable properties, good castability and resistance to corrosion play an important role. Aluminium alloys, constituting the combination of the low density and high strength are more and more often used in situations, where reduction of the subassembly element masses is significant, desired and feasible.
Characteristics of the mentioned mechanisms and their dependency has not only cognitive significance, but also enables to specify broader methodological and application perspectives of the presented aluminium cast alloys, which has a particular importance when the necessity of manufacturing of the engineering materials and elements that are executed on their basis on the request is clearly discussed. The analysis of the test results of the mechanical and usable properties as well as tests of the structure of the surface layer of aluminium alloys after thermal and surface processing will allow for specification of the conditions of the laser surface processing of the aluminium alloys, such as the rate of scanning, laser power, used within the scope from 1.0 up to 2.2 kW, type and rate of the powder feeding, in
order to produce the best possible surface layers on the surface of the processed alloys.
The highest demand for the aluminium alloys has been indicated and is still currently indicated by the automobile industry. The specific features of certain types of Al-Si alloys result in their particular fitness for strictly set applications, related to working conditions of the given elements e.g. for manufacturing of the pistons intended for internal-combustion engines and engines with high loads. Moreover, the aluminium alloys, the participation of which in the total mass of the motor vehicle presently amounts to circa 200 kg, are also used, inter alia, for the elements of the drive mechanism (pistons, transmission shafts, cylinder heads, cylinder blocks, gearboxes), elements of the body (vehicle frames and constructions, driver’s cabs, bonnets, doors, seat constructions, bumpers, cargo roof guides), elements of the chassis (braking systems, hoops, axles: rear and front) and other as semi-trailers, petrol tanks or heat exchangers.
An example of relatively new applications of aluminium alloys are body constructions that are entirely made of this kind of material, as e.g. spatial construction of Audi A8 body, enabling reduction of the vehicle mass by 40% in relation to the traditional frame made of steel [95]. In addition, 125 kg of the sheet metal, 70 kg of bars, 150 kg of casts and 40 kg of other aluminium forms accrue to the mass amounting to 385 kg of elements made of aluminium alloys used in the given vehicle. The priority goal of nearly all the companies, global consortiums and research centres along with the leading companies from China, USA and Europe is at present set to radically reduce emissions of the carbon oxide in the atmosphere, and what follows, to aim at reduction of the mass of construction and elements with simultaneous preservation or enhancement of their present properties. The need for reduction of the basic mass of the vehicles becomes so much more significant, that more and more transportation means are equipped with the so-called additional accessories (such as airbags, additional seatbelts, power window systems, etc.) increasing their mass, which aims not only at improvement of the traffic safety, but also at enhancement of the usable attractiveness of such vehicles.
Every kilogram of Al (2.7 g/cm3) substituting around 3 kg of steel (7.86 g/cm3), in the entire vehicle lifespan, makes economy amounting to approx. 20 kg CO2. Reduction of the weight of the average car size weighing 1400 kg results in reduction of the fuel consumption by 0.6 l at the distance amounting to 100 km [1].
Increased tests and multiple applications of the aluminium alloys in the constructions and other vehicle elements in the automobile industry will result in the possibility to reduce the average vehicle weight by around 300 kg, which, at average consumption of 7.2 l/100 km, gives economy in the amount of 3000 l in the entire lifespan of the given product and reduction of the exhaust fumes emissions by around 20%.
Aluminium alloys are at present one of the most frequently used construction materials of our century [2-4, 5-8], therefore it is very important to maintain high rate of the tests related to problems of the light alloys. Increasing the properties, particularly of the surface layer is however inextricably combined with application of appropriate technologies and methods for their formation. The methods making use of lasers are included within such technologies. Laser technologies play a vital role in the engineering of the surface of aluminium alloys. Lasers are type of devices that for many years have already been inextricably combined with improvement of the quality of our lives. What is more, their constant development, finding more recent forms of
their effici ease that t methadvan of the also T exper formmate perio frequ appli raw proce mostchem as by abovthe su whicproce of su the p particT layer (subs corro methprope Highand r low therm requi mentobtai partic appli abras durab differIn examproce decor of laL phystype manyecon (Fig. preci easy, of ex final energ
applications as iency, good qu
of automation o they become com hods, also includ
ntages related to e laser radiation The requirement including the rts, designers mation of the su
erials have to b od and high res uent cases the ec ication of the ne
materials are re essing of their su t often obtained mical, thermal-m y their mutual ve-mentioned pre urface layers of h found broa essing of the en ubstantial increas processed elemen The newly-deve cularly aim at m rs with properti strate), they con osive and decora hods particularl
erties and assura h hardness and c resistance to me (creeping and mal shock) and ired from the tioned propertie ined surface laye
cularly includi ication of thin sive wear and bility at low man
n order to prepa rent kinds of s mple aim at incre
essed aluminium rative properties Laser surface pr asers and their ical state of the
of the used pipe y other propertie omic issue. Th 1) and has to be ision of operati , nor a cheap tas xpensive compo costs of the mat gy in the form o
well as their u ality of the pro of the processes u mparable altern ding other surfa o their applicatio n, also within the
ts set for the p aluminium cast and engineers urface layers pro
e characterised sistance to corr conomic reasons
ew, better mate eplaced with ch urface. The prop d by means of mechanical and m
combinations erequisites, new f aluminium allo ad application ngineering mate se of the mecha nts.
eloped and cu manufacturing, t ies that are dif ncern mainly t ative properties. ly regards enh ance of high res
castability as w echanical impac frail creeping) d adequate therm
manufactured es depend main
ers. Recent surf ing laser tech
coatings from corrosion shou nufacturing cost are the basis ma supportive techn easing the absor m surfaces, impro
s of the surface l ocessing denote modifications a e active medium es, resonators, le es. The main as he laser is used
e characterised b ion. Constructin
sk, due to the fa onent materials, terial processing of the laser. Amo
undoubted advan ocessed element using lasers), re ative to tradition face technologie
on result in mor e scope of surfac present engineer t alloys, force to seek new operties, due to by the required osion. Neverthe
determine manu erials, therefore
heaper ones afte perties of the sur thermal process mechanical proc
[16-23]. With technologies fo oys started to be
during modi rials, ensuring t anical and usable urrently designe testing and usin fferent, better t the abrasion res . Problems of u hancement of istance to chem well as high fatig
ct, and resistanc temperatures ( mal conductivit surface layer. nly on the stru face engineering
hniques and hard materials uld also ensur aterial for the lass. nologies are use rption of laser ra ovement of anti- layers of alumini es mainly the las are all differen m, its chemical ength of the ligh spect limiting th d in the materia by high power, ng of such a la act that it requir at the same tim g with the use of
ong lasers that a
ntages (energy ts, selectivity, sult in the fact nal processing es [9-15]. The e frequent use e processing. ring materials,
the materials methods for o the fact that d exploitation eless, in most ufacturing and the expensive er appropriate rface layer are sing, thermal- essing as well regard to the r formation of implemented, ification and the possibility e properties of ed techniques ng the surface than the core sistance, anti-
se of the new the strength ical influence. gue resistance ce to high and (including the ty are mainly The above- ucture of the g technologies, methods for s, resistant to re appropriate ser techniques ed, which for adiation of the -corrosive and ium alloys. ser. The types
t in terms of composition, ht emitted and heir use is the al engineering efficiency and aser is neither res application me increasing f the source of are most often
used for p medium is following o x solid sta x gas las
lasers), x semicon x liquid la x plasma x free-ele x X-ray a
Fig. 1 L In case application 21% to mar soldering, h main advan as much as used for cu soldering a 106 W/cm semiconduc type of d construction types of las the first la 1927, elec developed possibility chemical co
Diode l Laser), du manufactur of emitted l in many br used for rea pump syste disc), in sto in laser th properties o materials be Diode l of the beam are stable a
processing of t a solid body ones [15,24,25]: ate lasers (crysta sers (atom, mol nductor lasers (d asers (dye, chem
lasers, ectron lasers, and gamma ray l
Laser techniques of laser process , as high as 37% rking, 18% to m hardening and ntage of the laser
s 1030 W/cm2, utting, marking and surface proc m2. One of the ctor laser, also device, characte
n, as well as in sers. Despite the asers that have ctroluminescenc and modified a of miniaturisatio omposition of th lasers, also inclu ue to their sm ring costs (as for lengths of the el ranches of ever ading of data fro ems for differen omatology and o hroughing and g
of the metal, po elong to such ap lasers are charac m focus with m and easy to con
the engineering or gas, and the alline (ruby), gla lecular, ion, ex diode lasers), mical),
asers.
used for materia sing of the mate
% falls to cutting microprocessing,
surfacing and 2 rs is concentratio , such extensive and perforation cessing power d e most recent called diode las erised by man its functioning fact that these l ever been disc ce phenomenon
all the time, in on and very prec he semiconductor uding HPDL las mall dimensions
r industrial cond ectromagnetic w ryday life and e
om optical drive nt types of laser
rthodontics in th gingivectomy, s olymer, compos pplications.
cterised by recta multimodal distri
ntrol. Lack of co
g materials the eir main types ass (neodymium) xcimer, copper
al treatment [26- erials the most f g of the materia 16% to welding 2% to perforatio on of energy am e power is part n. In case of w density does not variants of la ser, which is a ny differences in comparison t lasers are the on overed (O.W. à n), they have n particular due cise modification
rs used. ers (High Power s and relative ditions) and wid waves found app engineering. The
es CD, DVD, B s (e.g. Nd-YAG he treatments con shaping of the
ite, as well as c angular or linea ibution of energ omplex optical s
active are the ), vapour
-31] frequent als, then g, 6% to on. The mounting ticularly welding, exceed asers is specific in its to other nes from àosiew, e been e to the n of the r Diode ly low de range plication e lasers lue-ray, G, fibre, nsisting surface ceramic ar shape gy, they systems
1. Introduction
1.Introduction
While analysing the given element in terms of its internal structure as well as possible, future working conditions it should be remembered that the product properties depend mainly on two factors: internal structure of the material, from which it has been made and on the condition of the external surface having both direct mechanical and chemical contact with the environment, including inter alia with the tools processing the given element, as well as during exploitation with the surfaces of other co-operating elements. The character of the surface, its morphology and properties often have direct impact on the product manufacturing, and in the most cases the surface quality decides just on its functional qualities. The surface layer of the material is characterised not only by its shape, roughness and appearance (colour, transparency), but also by a number of other properties that are completely different from the properties of the inside of the material, which in a significant manner influence the various types of mechanisms occurring around its area, i.e.: friction, fatigue, corrosion, erosion, diffusion, conductivity and determine the usability and fitness of the surface processed elements for possible uses. Despite the fact that the surface layer of the engineering materials may not be formed independently from the substrate, nevertheless the requirements set to the inside of the product are usually different from the conditions that are expected from the manufactured surfaces. Often due to economic, technological or even practical reasons it is more advantageous to select the substrate in such a way that it would conform to the general resistance assumptions anticipated for the given element, and as a next step to apply one of the techniques for its surface treatment in order to protect it against destruction or to enhance its usable properties. Therefore the material selection constitute such an important stage of design, which is often executed due to destructive processes present during the given work environment.
Attention should also be paid to the fact that formation of the new materials, including also the ones with the applied coating, carries the possibility of discovering the pioneering, previously unidentified structural and wear mechanisms or specification of broader scope of the already existing mechanisms.
In relation to the current market demand for light and reliable constructions, aluminium alloys, belonging to the group of the construction materials, characterised by a number of good mechanical and usable properties, good castability and resistance to corrosion play an important role. Aluminium alloys, constituting the combination of the low density and high strength are more and more often used in situations, where reduction of the subassembly element masses is significant, desired and feasible.
Characteristics of the mentioned mechanisms and their dependency has not only cognitive significance, but also enables to specify broader methodological and application perspectives of the presented aluminium cast alloys, which has a particular importance when the necessity of manufacturing of the engineering materials and elements that are executed on their basis on the request is clearly discussed. The analysis of the test results of the mechanical and usable properties as well as tests of the structure of the surface layer of aluminium alloys after thermal and surface processing will allow for specification of the conditions of the laser surface processing of the aluminium alloys, such as the rate of scanning, laser power, used within the scope from 1.0 up to 2.2 kW, type and rate of the powder feeding, in
order to produce the best possible surface layers on the surface of the processed alloys.
The highest demand for the aluminium alloys has been indicated and is still currently indicated by the automobile industry. The specific features of certain types of Al-Si alloys result in their particular fitness for strictly set applications, related to working conditions of the given elements e.g. for manufacturing of the pistons intended for internal-combustion engines and engines with high loads. Moreover, the aluminium alloys, the participation of which in the total mass of the motor vehicle presently amounts to circa 200 kg, are also used, inter alia, for the elements of the drive mechanism (pistons, transmission shafts, cylinder heads, cylinder blocks, gearboxes), elements of the body (vehicle frames and constructions, driver’s cabs, bonnets, doors, seat constructions, bumpers, cargo roof guides), elements of the chassis (braking systems, hoops, axles: rear and front) and other as semi-trailers, petrol tanks or heat exchangers.
An example of relatively new applications of aluminium alloys are body constructions that are entirely made of this kind of material, as e.g. spatial construction of Audi A8 body, enabling reduction of the vehicle mass by 40% in relation to the traditional frame made of steel [95]. In addition, 125 kg of the sheet metal, 70 kg of bars, 150 kg of casts and 40 kg of other aluminium forms accrue to the mass amounting to 385 kg of elements made of aluminium alloys used in the given vehicle. The priority goal of nearly all the companies, global consortiums and research centres along with the leading companies from China, USA and Europe is at present set to radically reduce emissions of the carbon oxide in the atmosphere, and what follows, to aim at reduction of the mass of construction and elements with simultaneous preservation or enhancement of their present properties. The need for reduction of the basic mass of the vehicles becomes so much more significant, that more and more transportation means are equipped with the so-called additional accessories (such as airbags, additional seatbelts, power window systems, etc.) increasing their mass, which aims not only at improvement of the traffic safety, but also at enhancement of the usable attractiveness of such vehicles.
Every kilogram of Al (2.7 g/cm3) substituting around 3 kg of steel (7.86 g/cm3), in the entire vehicle lifespan, makes economy amounting to approx. 20 kg CO2. Reduction of the weight of the average car size weighing 1400 kg results in reduction of the fuel consumption by 0.6 l at the distance amounting to 100 km [1].
Increased tests and multiple applications of the aluminium alloys in the constructions and other vehicle elements in the automobile industry will result in the possibility to reduce the average vehicle weight by around 300 kg, which, at average consumption of 7.2 l/100 km, gives economy in the amount of 3000 l in the entire lifespan of the given product and reduction of the exhaust fumes emissions by around 20%.
Aluminium alloys are at present one of the most frequently used construction materials of our century [2-4, 5-8], therefore it is very important to maintain high rate of the tests related to problems of the light alloys. Increasing the properties, particularly of the surface layer is however inextricably combined with application of appropriate technologies and methods for their formation. The methods making use of lasers are included within such technologies. Laser technologies play a vital role in the engineering of the surface of aluminium alloys. Lasers are type of devices that for many years have already been inextricably combined with improvement of the quality of our lives. What is more, their constant development, finding more recent forms of
their effici ease that t methadvan of the also T exper formmate perio frequ appli raw proce mostchem as by abovthe su whicproce of su the p particT layer (subs corro methprope Highand r low therm requi mentobtai partic appli abras durab differIn examproce decor of laL phystype manyecon (Fig.
preci easy, of ex final energ
applications as iency, good qu
of automation o they become com hods, also includ
ntages related to e laser radiation The requirement including the rts, designers mation of the su
erials have to b od and high res uent cases the ec ication of the ne
materials are re essing of their su t often obtained mical, thermal-m y their mutual ve-mentioned pre urface layers of h found broa essing of the en ubstantial increas processed elemen The newly-deve cularly aim at m rs with properti strate), they con osive and decora hods particularl erties and assura h hardness and c resistance to me (creeping and mal shock) and
ired from the tioned propertie ined surface laye cularly includi ication of thin sive wear and bility at low man n order to prepa rent kinds of s mple aim at incre
essed aluminium rative properties Laser surface pr asers and their ical state of the
of the used pipe y other propertie omic issue. Th 1) and has to be ision of operati , nor a cheap tas xpensive compo costs of the mat gy in the form o
well as their u ality of the pro of the processes u mparable altern ding other surfa o their applicatio n, also within the
ts set for the p aluminium cast and engineers urface layers pro
e characterised sistance to corr conomic reasons
ew, better mate eplaced with ch urface. The prop d by means of mechanical and m
combinations erequisites, new f aluminium allo ad application ngineering mate se of the mecha nts.
eloped and cu manufacturing, t ies that are dif ncern mainly t ative properties.
ly regards enh ance of high res castability as w echanical impac frail creeping) d adequate therm
manufactured es depend main
ers. Recent surf ing laser tech
coatings from corrosion shou nufacturing cost are the basis ma supportive techn easing the absor m surfaces, impro
s of the surface l ocessing denote modifications a e active medium es, resonators, le es. The main as he laser is used
e characterised b ion. Constructin
sk, due to the fa onent materials, terial processing of the laser. Amo
undoubted advan ocessed element using lasers), re ative to tradition face technologie
on result in mor e scope of surfac present engineer t alloys, force to seek new operties, due to by the required osion. Neverthe
determine manu erials, therefore
heaper ones afte perties of the sur thermal process mechanical proc
[16-23]. With technologies fo oys started to be
during modi rials, ensuring t anical and usable urrently designe testing and usin fferent, better t the abrasion res . Problems of u hancement of istance to chem well as high fatig
ct, and resistanc temperatures ( mal conductivit surface layer.
nly on the stru face engineering
hniques and hard materials uld also ensur aterial for the lass.
nologies are use rption of laser ra ovement of anti- layers of alumini es mainly the las are all differen m, its chemical ength of the ligh spect limiting th d in the materia by high power, ng of such a la act that it requir at the same tim g with the use of
ong lasers that a
ntages (energy ts, selectivity, sult in the fact nal processing es [9-15]. The e frequent use e processing.
ring materials, the materials methods for o the fact that d exploitation eless, in most ufacturing and the expensive er appropriate rface layer are sing, thermal- essing as well regard to the r formation of implemented, ification and the possibility e properties of ed techniques ng the surface than the core sistance, anti-
se of the new the strength ical influence.
gue resistance ce to high and (including the ty are mainly The above- ucture of the g technologies, methods for s, resistant to re appropriate ser techniques ed, which for adiation of the -corrosive and ium alloys.
ser. The types t in terms of composition, ht emitted and heir use is the al engineering efficiency and aser is neither res application me increasing f the source of are most often
used for p medium is following o x solid sta x gas las
lasers), x semicon x liquid la x plasma x free-ele x X-ray a
Fig. 1 L In case application 21% to mar soldering, h main advan as much as used for cu soldering a 106 W/cm semiconduc type of d construction types of las the first la 1927, elec developed possibility chemical co
Diode l Laser), du manufactur of emitted l in many br used for rea pump syste disc), in sto in laser th properties o materials be Diode l of the beam are stable a
processing of t a solid body ones [15,24,25]:
ate lasers (crysta sers (atom, mol nductor lasers (d asers (dye, chem
lasers, ectron lasers, and gamma ray l
Laser techniques of laser process , as high as 37%
rking, 18% to m hardening and ntage of the laser
s 1030 W/cm2, utting, marking and surface proc m2. One of the ctor laser, also device, characte
n, as well as in sers. Despite the asers that have ctroluminescenc and modified a of miniaturisatio omposition of th lasers, also inclu ue to their sm ring costs (as for lengths of the el ranches of ever ading of data fro ems for differen omatology and o hroughing and g
of the metal, po elong to such ap lasers are charac m focus with m and easy to con
the engineering or gas, and the alline (ruby), gla lecular, ion, ex diode lasers), mical),
asers.
used for materia sing of the mate
% falls to cutting microprocessing,
surfacing and 2 rs is concentratio , such extensive and perforation cessing power d
e most recent called diode las erised by man
its functioning fact that these l ever been disc ce phenomenon
all the time, in on and very prec he semiconductor uding HPDL las mall dimensions
r industrial cond ectromagnetic w ryday life and e om optical drive nt types of laser
rthodontics in th gingivectomy, s olymer, compos pplications.
cterised by recta multimodal distri
ntrol. Lack of co
g materials the eir main types ass (neodymium) xcimer, copper
al treatment [26- erials the most f g of the materia 16% to welding 2% to perforatio on of energy am e power is part n. In case of w density does not variants of la ser, which is a ny differences in comparison t lasers are the on overed (O.W. à n), they have n particular due cise modification
rs used.
ers (High Power s and relative ditions) and wid waves found app engineering. The es CD, DVD, B
s (e.g. Nd-YAG he treatments con shaping of the
ite, as well as c angular or linea ibution of energ omplex optical s
active are the ), vapour
-31]
frequent als, then g, 6% to on. The mounting ticularly welding, exceed asers is specific in its to other nes from àosiew, e been e to the n of the r Diode ly low de range plication e lasers lue-ray, G, fibre, nsisting surface ceramic ar shape gy, they systems
causi energ manuadvan makedistri proce densi are th appli advan used mateT semiclean Amoof th follow and appli and p
Fig.
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use o trans of su absor place lengt of in coeff techn way, to be densi differF
x R
lam sf
ing substantial l gy efficiency re ufacturing techn ntages of HDPL es it a very attr ibution of the essed materials ity of the beam b he basic advanta ication of the m
ntages result in for modificatio erials [32].
There are ma conductor laser ning the surfac ong the main tec
he engineering wing ones may b
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on of laser sur Technologies, Inc
f lasers used in f the focused ra s. The radiant flu s often subject to ount of heat abs he beam depend ty of the radiatio material by the b diation enables t r example harde ew technologies
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rface treatment, c)
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surface improv materia lasers, d fed to t fusion impulse x During form of beam ra and hyd same ti area. G lasers a power d and me known The wo surface lay use of HPD developmen industry inc maintain hi new researc
Fig. 3. Tim treatment material
with no modifica of total melting uence, enables t n and corrosion.
alloying consis ts to the materia drodynamic mix on is the fact tha state. The laser g and formation
tional movemen eam the material erial is formed a dy in the solid st nt, gradient of t, as well as on t is a one-stage m layer in th ement of the p al. Fusion is real due to the fact t the melted zone is not performe es. melting (surfaci f the powder or adiation in the g drogen is most o ime as a gas fo Gas lasers CO2, c
are most frequ density (up to 1 elting, allowing construction ma orks related to yer of materials, DL laser, are su
nt of technolog creases systemat igh rate of resear ch areas (Fig. 3)
me axis presenti development in
ation of the chem g of the process
to achieve high sts in introduc al being subject t xing of both m at at least one of beam affecting n of a pool, in nts, convections ls mix with each t the periphery o tate depends mai the concentra the time of diffu method, which ai e form of a properties of the lised by means o that the strength e only at the mo ed during the br ing) additional m r wire by means gas shield. Argon
often used as a s r feeding the p continuous Nd:Y uently used for
07 W/cm2) enab g for practical aterials [34-37, 2
technologies fo including light ubstantial at a gl gy and laser d tically, therefore rch over this pro .
ing the “mile st n relations to
mical compositi sed material an resistance to ab ction of the a to processing by materials. A ne f these materials
the material ca which, as a re s and pressure h other and a ne of the pool. Allo inly on the temp ation of the di sion [9,12-15].
ims at achievem a quasi-compos
e layer of the of continuous-op hening material oment of laser h reaks between t material is melte s of energy of th
n or a mixture o shielding gas an owder to the su YAG lasers and laser surfacing ble very precise
evaporation of 29-32].
or modification metal alloys, w lobal scale. The
devices at the e it is very impo oblems and to po
tones” of laser the applied su
ion as a nd, as a brasion, alloying y means ecessary s is in a auses its esult of of the ew layer oying of perature iffusing ment of a site or alloyed peration may be heating, the heat ed in the he laser of argon nd at the urfacing d HPDL g. High heating all the of the with the rate of global ortant to oint out
surface ubstrate
alloy given have with alumAlSi4 basic 850±and atmooxyg pouri been streamT matewhic The s used 5°C/m
Fig. alum
Table Chem
Table Heat D
1. Materia
The presented t ys AlSi9Cu and n in the Table 1
been used (Figs The tested alloy ceramic mixin minium cast allo 49 and two-com c components th
±10 ºC, and then heating of the osphere of argon gen and nitrogen
ing the ingots in additionally sub The samples ha
m to the entire erial 3 ingots hav h have been su standard therma in the electric min, along to the
4. Scheme o minium alloys
e 1.
mical compositio Alloy
ACAlSi9Cu ACAlSi9Cu4
e 2.
treatment condi Description of th
Solution h ag
al vel. invest
test results conc d AlSi9Cu4 wit
1. As a reinforc s. 5-8).
ys have been me ng the basic c oys with silicon mponent alloy A he alloy has been n kept in this tem e alloy has be n for limitation
n from the atm ntended for the te
bject to carbonis ave been poure e volume of th ve been made w ubject to therma
l processing of t c resistant furna
e established sch
f the heat tre
on of the analyse
Si 9.09 9.27
itions for the inv he heat treatment
heat treatment geing
tigations
cern experiment th the chemical cing material ca
elted in the indu omponents at p n, two-componen AlCu55. After m n heated to the t mperature for 2 h
een made in t of the diffusion mosphere. Immed
ests every melte sation by mean s ed with constan he ingot. From with an average m
al and mechani the aluminium a ace U117, with heme (Fig. 4).
eatment of the
ed aluminium all Mass co Cu 1.05 4.64
vestigated alumin t step
Tem
tal aluminium l composition arbon powders uction furnace proper ratios: nt basic alloy melting of the temperature of hours. Melting the protective n of hydrogen, diately before ed material has
of argon. nt, continuous
each melted mass of 15 kg, cal treatment. lloys has been h heating rate
e investigated
loys
oncentration of th Fe 0.72 0.17
nium alloys
mperature, °C 505 170
During temperature treatment q the materia The withst heat treat 170°C for constituted been surfac Alumin characterise matrix and which morp and copper AlSi9Cu4 a with sharp- relation to e structure of acerous form near eutec additionally presumably phase Al2C separate fo reagents dy
The ta means of th range 1-10 the melted the fluidisa been conne feeding noz to protect t of laser fu properties o and ZrO2 w as alloying
he alloying elem Mn 0.36 0.01
Heat Time, 10 12
g heating isoth e of 450°C fo quenching at wat
al has been quen tand temperatur
505°C for 10 h 12 hours (Table
a reference po ce processed. nium cast alloys
ed by the structur discontinuous p phology depend r. It has been p a phase ȕ-Si occ -edge corners lo each other in a d f the tested allo mations of the p ctics Į+Al2Cu+ y include the y Al15(FeMn)3Si2
Cu occurs as a ormations of irr
es brown. arget laser fusio
he technique of g/min in a conti metal by means ation or gravita
ected to the tra zzle. Fusion has the substrate aga usion has been of the tested allo with the properti
material.
ments in the inves Mg
0.27 0
0.28 0
t treatment condi h
hermal break h or 15 minutes ter has been use nched on air at re amounted res hours, and for e 2). Alloys afte
int in relation t AlSi9Cu and Al re of the solid so phase ȕ-Si formi ds on the mass c proved that in th urs in the form cated in the ma disorganised man oys is character
hase Al5FeSi, w +AlCuMgSi+ȕ,
phase with fe
2. In the tested c component of regular shapes, n and remelting f feeding the pow
nuous manner to of dosing the gr tional feeder. T ansporting gas
been made in th ainst oxidising.
made so as t oys, ceramic po es given in the T
stigated alloys in
Zn A
0.14 88
0.05 8
itions
Cooli w (temperature of A
has been used . After solutio d, whereas after the room temp spectively for s the subsequent r the thermal tre to the alloys th lSi9Cu4 (Figs. 9 olution Į constitu ing eutectic grai concentration of he alloys AlSi9 of large irregula atrix at high dist nner. What is m rised by occurre which are usually which eutectic rrum and man cast alloys Al-Si triple eutectics which with th g has been execu
wder at rate wit o the area of the ranulate with the The powder fee
cylinder and p he argon shield, i The surface pro to improve the wders WC, SiC Table 3 have be
n %
Al R
8.17 0.
5.4 0.
ing type water
Air
f the environmen at the on heat r ageing perature. solution ageing eatment hat have -12) are uting the ns Į+ȕ, f silicon Cu and ar plates tance in more, the ence of located cs may nganese, i-Cu the and as he used uted by thin the pool of e use of der has powder-
in order ocessing usable C, Al2O3
en used
Rest .15 .18
nt)
causi energ manuadvan makedistri proce densi are th appli advan used mateT semiclean Amoof th follow and appli and p
Fig.
Surfa
use o trans of su absor place lengt of in coeff techn way, to be densi differF
x R
lam sf
ing substantial l gy efficiency re ufacturing techn ntages of HDPL es it a very attr ibution of the essed materials ity of the beam b he basic advanta ication of the m
ntages result in for modificatio erials [32].
There are ma conductor laser ning the surfac ong the main tec he engineering
wing ones may b surfacing. One ications with the particularly laser
2 Classificatio ace Treatment T The majority of of absorption of sparent materials uch a material is rption. The amo e of falling of th th, power densit nfluencing the m
ficient. Laser rad nologies, as for
or introduce ne e realised with ity [32,33].
Four basic met rentiated: remelt Remelting consi aser beam radia method allows f structure in the formation of che
losses of energy eaching 50% an nology may also L laser. At the s
ractive tool in s laser beam fo and possibilit by HPDL lasers ages in favour o material engine n the fact that on of the surfa any possibilitie rs in the materi
es, soldering, w chniques that ar
materials with be included: rem e of the most e use of the dio r fusion and rem
on of laser sur Technologies, Inc f lasers used in f the focused ra s. The radiant flu s often subject to ount of heat abs he beam depend ty of the radiatio material by the b diation enables t r example harde ew technologies the use of the thods for laser
ting, alloying, fu ists in melting o ation without us for substantial m
surface layer o emically uniform
y from 10 up t nd ease of robot o be included t ame time it is r surface engineer ocus on the su ty to generate s in comparison of the semicondu eering. The abo
HPDL lasers a ace layers of th
es of applica al engineering, welding, remelt e used for surfa the use of di melting, alloying developing an de laser is surfa melting of the ligh
rface treatment, c)
the material pro adiation through ux while falling o partial reflecti sorbed by the m s on the laser ra on falling on the beam and radiati to realise the pre ening, in a bett , e.g. laser fusio e devices with surface proce usion and surfac of the material ing additional m modification of t of the materials m and fine-cryst
to 30%, high- tisation of the to consecutive eliable, which ring. Uniform urface of the lower power to other lasers uctor lasers in ove-mentioned are frequently he engineering ation of the inter alia for ting (Fig. 2).
ace processing ode laser the g and/or fusion nd innovative ace processing
ht alloys.
(according to
ocessing make h various non-
on the surface ion and partial material at the adiation wave- e surface, time
ion absorption esently known ter or quicker on, impossible lower power ssing can be ing.
by energy of materials. This the crystalline by means of talline surface
layer w result o consequ erosion x Laser
element of hyd conditio liquid s melting gravitat laser be of mate the bod gradien element x Fusion
surface improv materia lasers, d fed to t fusion impulse x During form of beam ra and hyd same ti area. G lasers a power d and me known The wo surface lay use of HPD developmen industry inc maintain hi new researc
Fig. 3. Tim treatment material
with no modifica of total melting uence, enables t n and corrosion.
alloying consis ts to the materia drodynamic mix on is the fact tha state. The laser g and formation
tional movemen eam the material erial is formed a dy in the solid st nt, gradient of t, as well as on t is a one-stage m
layer in th ement of the p al. Fusion is real due to the fact t the melted zone is not performe es. melting (surfaci f the powder or adiation in the g drogen is most o ime as a gas fo Gas lasers CO2, c
are most frequ density (up to 1 elting, allowing construction ma orks related to yer of materials, DL laser, are su
nt of technolog creases systemat igh rate of resear ch areas (Fig. 3)
me axis presenti development in
ation of the chem g of the process
to achieve high sts in introduc al being subject t xing of both m
at at least one of beam affecting n of a pool, in nts, convections ls mix with each t the periphery o tate depends mai the concentra the time of diffu method, which ai e form of a properties of the lised by means o that the strength e only at the mo ed during the br ing) additional m r wire by means gas shield. Argon
often used as a s r feeding the p continuous Nd:Y uently used for
07 W/cm2) enab g for practical
aterials [34-37, 2 technologies fo including light ubstantial at a gl gy and laser d tically, therefore rch over this pro .
ing the “mile st n relations to
mical compositi sed material an resistance to ab ction of the a to processing by materials. A ne f these materials the material ca
which, as a re s and pressure h other and a ne of the pool. Allo inly on the temp ation of the di sion [9,12-15].
ims at achievem a quasi-compos
e layer of the of continuous-op hening material
oment of laser h reaks between t material is melte s of energy of th
n or a mixture o shielding gas an
owder to the su YAG lasers and laser surfacing ble very precise
evaporation of 29-32].
or modification metal alloys, w lobal scale. The
devices at the e it is very impo oblems and to po
tones” of laser the applied su
ion as a nd, as a brasion, alloying y means ecessary s is in a auses its esult of of the ew layer oying of perature iffusing ment of a site or alloyed peration may be heating, the heat ed in the he laser of argon nd at the urfacing d HPDL g. High heating all the of the with the rate of global ortant to oint out
surface ubstrate
alloy given have with alumAlSi4 basic 850±and atmooxyg pouri been streamT matewhic The s used 5°C/m
Fig.
alum
Table Chem
Table Heat D
1. Materia
The presented t ys AlSi9Cu and n in the Table 1
been used (Figs The tested alloy
ceramic mixin minium cast allo 49 and two-com c components th
±10 ºC, and then heating of the osphere of argon gen and nitrogen ing the ingots in
additionally sub The samples ha m to the entire erial 3 ingots hav h have been su standard therma
in the electric min, along to the
4. Scheme o minium alloys
e 1.
mical compositio Alloy
ACAlSi9Cu ACAlSi9Cu4
e 2.
treatment condi Description of th
Solution h ag
al vel. invest
test results conc d AlSi9Cu4 wit
1. As a reinforc s. 5-8).
ys have been me ng the basic c oys with silicon mponent alloy A he alloy has been n kept in this tem e alloy has be n for limitation
n from the atm ntended for the te
bject to carbonis ave been poure e volume of th ve been made w ubject to therma
l processing of t c resistant furna
e established sch
f the heat tre
on of the analyse
Si 9.09 9.27
itions for the inv he heat treatment
heat treatment geing
tigations
cern experiment th the chemical cing material ca elted in the indu omponents at p n, two-componen AlCu55. After m n heated to the t mperature for 2 h een made in t of the diffusion mosphere. Immed
ests every melte sation by mean s ed with constan
he ingot. From with an average m
al and mechani the aluminium a ace U117, with heme (Fig. 4).
eatment of the
ed aluminium all Mass co Cu 1.05 4.64
vestigated alumin t step
Tem
tal aluminium l composition arbon powders uction furnace proper ratios:
nt basic alloy melting of the temperature of hours. Melting the protective n of hydrogen, diately before ed material has
of argon.
nt, continuous each melted mass of 15 kg, cal treatment.
lloys has been h heating rate
e investigated
loys
oncentration of th Fe 0.72 0.17
nium alloys
mperature, °C 505 170
During temperature treatment q the materia The withst heat treat 170°C for constituted been surfac Alumin characterise matrix and which morp and copper AlSi9Cu4 a with sharp- relation to e structure of acerous form near eutec additionally presumably phase Al2C separate fo reagents dy
The ta means of th range 1-10 the melted the fluidisa been conne feeding noz to protect t of laser fu properties o and ZrO2 w as alloying
he alloying elem Mn 0.36 0.01
Heat Time, 10 12
g heating isoth e of 450°C fo quenching at wat al has been quen tand temperatur
505°C for 10 h 12 hours (Table
a reference po ce processed.
nium cast alloys ed by the structur discontinuous p phology depend r. It has been p a phase ȕ-Si occ -edge corners lo each other in a d f the tested allo mations of the p ctics Į+Al2Cu+
y include the y Al15(FeMn)3Si2
Cu occurs as a ormations of irr
es brown.
arget laser fusio he technique of
g/min in a conti metal by means ation or gravita
ected to the tra zzle. Fusion has the substrate aga usion has been of the tested allo with the properti
material.
ments in the inves Mg
0.27 0
0.28 0
t treatment condi h
hermal break h or 15 minutes ter has been use nched on air at re amounted res hours, and for e 2). Alloys afte
int in relation t AlSi9Cu and Al re of the solid so phase ȕ-Si formi ds on the mass c proved that in th urs in the form cated in the ma disorganised man oys is character
hase Al5FeSi, w +AlCuMgSi+ȕ,
phase with fe
2. In the tested c component of regular shapes, n and remelting f feeding the pow
nuous manner to of dosing the gr tional feeder. T ansporting gas
been made in th ainst oxidising.
made so as t oys, ceramic po es given in the T
stigated alloys in
Zn A
0.14 88
0.05 8
itions
Cooli w (temperature of A
has been used . After solutio d, whereas after the room temp spectively for s the subsequent r the thermal tre to the alloys th lSi9Cu4 (Figs. 9 olution Į constitu
ing eutectic grai concentration of he alloys AlSi9 of large irregula atrix at high dist nner. What is m rised by occurre which are usually which eutectic rrum and man cast alloys Al-Si triple eutectics which with th g has been execu
wder at rate wit o the area of the ranulate with the The powder fee
cylinder and p he argon shield, i The surface pro to improve the wders WC, SiC Table 3 have be
n %
Al R
8.17 0.
5.4 0.
ing type water
Air
f the environmen at the on heat r ageing perature.
solution ageing eatment hat have -12) are uting the ns Į+ȕ, f silicon Cu and ar plates tance in more, the ence of located cs may nganese, i-Cu the and as he used uted by thin the pool of e use of der has powder-
in order ocessing usable C, Al2O3
en used
Rest .15 .18
nt)
2. Material vel. investigations
Fig
Fig the mIn as a irregu at th execu scope surfa Withof fe amouto 3 prove impaB melti for th been
g. 5. Surface mor
. 7. Surface morp n case of directi melted area, blow
consequence of ular shapes, with he sides of the
uted samples fo e of the experim ace of the samp h regard to the a
eding the additio unt of flow of th
l/s. On the bas ed that the sha act on the correct Based on the v ing of the surfac he substrate mat established with
rphology of the t
phology of the alu ing too excessive wing of the liqu f achievement of h characteristic n
stitch, which or further stage ments adequate d
ple has been sel above-mentioned onal material to he carrier has be sis of the prelim ape of the appl
t fusion of partic visual inspection ce layer the optim terial of the alu hin the range fro
tungsten carbide
uminium oxide po e blow of the pro uid metal pool to f the remelting f
new layers of th automatically e of tests. Therefo distance of the no lected, amountin d assumptions a the liquid pool, een experimental minary tests it h lied nozzle has cles of the ceram n of the macro mum values of th minium alloy A om 1.0 kW up to
e powder (SEM)
owder (SEM) otective gas in ook place and face with very he liquid metal eliminated the ore within the ozzle from the ng to 20 mm.
and continuity the minimum lly established has also been a substantial mic powders.
o structure of he laser power AlSi9Cu4 have o 2.0 kW, and
Fig. 6. Surfac
Fig. 8. Surfac adequate ra tested alum 0.5 m/min u rate of reme preliminary and the rat the tests. Th time, durin the same t absorbed by of the exten and too low formation o fusion rate characterise in the matri in lack of in
ce morphology o
ce morphology o ate of fusion and minium alloys
up to 1.0 m/min elting and fusion y trial runs the la
e of powder fus he increase of th g which the lase time results in y the substrate a nt of the structur w scanning rate of craters, wher e may be th ed by inhomogen ix of the alumini nterfusion.
of the silicon car
of the circonium d remelting of t (Figs. 9-12) w n. It has been s n amounts to 0.5 aser power withi sion 0.5 m/min he rate of fusion er beam influenc
limitation of t and as a consequ
ral changes. Usin causes evapora eas using too lo e reason for neous distributio ium cast alloys A
rbide powder (SE
oxide powder ( the surface layer within the rang
tated that the op 5 m/min, therefo in the range 1.5- have been adop causes reduction ces the material the amount of uence leads to lim
ng too high laser ation of the surfa ow power and to inadequate re on of the particle Al-Si-Cu, or ma
EM)
SEM) r of the ge from ptimum ore after -2.0 kW pted for n of the , and at energy mitation r power face and oo high melting es fused ay result
Figcast
Figage
Table
g. 9. Microstruct t state
g. 11. Microstruc eing
e 3. Properties o
D Hard Melti Boilin Radiation r
Thermal Crystallogr
ture of the cast a
cture of the cast
of the ceramic po Properties Density, g/cm3 dness HV, Kg/mm
ng temperature, ng temperature, refraction coeffi transmition, Wm raphic structure,
Colour
aluminium alloy
aluminium alloy
owders used for
m2
°C
°C cient, nD
m-1K-1 unit cell
y AlSi9Cu in as
y AlSi9Cu after
feeding WC 15.69
2400 2870 6000 3.19 84 heksagon
regular black
Fig. 10. Mic as cast state
r Fig. 12. Mic after ageing
nal r
montetr gu w
rostructure of th
crostructure of
ZrO2
5.68 1100
2715 D
4300 2.13 2 nocrlinic ragonal,
ularna white
he cast aluminiu
the cast alumin
SiC 3.44 2800 Decomposition in
2700 sublimation
2.55 120 regular
gray
um alloy AlSi9C
nium alloy AlS
Al2O3
3.97 2300
n 2047
2977 1.76 30 trigona
white Cu4 in
i9Cu4
al
Fig
Fig the mIn as a irregu at th execu scope surfa Withof fe amouto 3 prove impaB melti for th been
g. 5. Surface mor
. 7. Surface morp n case of directi melted area, blow
consequence of ular shapes, with he sides of the
uted samples fo e of the experim ace of the samp h regard to the a eding the additio unt of flow of th
l/s. On the bas ed that the sha act on the correct Based on the v ing of the surfac he substrate mat established with
rphology of the t
phology of the alu ing too excessive wing of the liqu f achievement of h characteristic n
stitch, which or further stage ments adequate d ple has been sel above-mentioned onal material to he carrier has be sis of the prelim ape of the appl
t fusion of partic visual inspection ce layer the optim terial of the alu hin the range fro
tungsten carbide
uminium oxide po e blow of the pro uid metal pool to f the remelting f
new layers of th automatically e of tests. Therefo distance of the no lected, amountin d assumptions a the liquid pool, een experimental minary tests it h lied nozzle has cles of the ceram n of the macro mum values of th minium alloy A om 1.0 kW up to
e powder (SEM)
owder (SEM) otective gas in ook place and face with very he liquid metal eliminated the ore within the ozzle from the ng to 20 mm.
and continuity the minimum lly established has also been a substantial mic powders.
o structure of he laser power AlSi9Cu4 have o 2.0 kW, and
Fig. 6. Surfac
Fig. 8. Surfac adequate ra tested alum 0.5 m/min u rate of reme preliminary and the rat the tests. Th time, durin the same t absorbed by of the exten and too low formation o fusion rate characterise in the matri in lack of in
ce morphology o
ce morphology o ate of fusion and minium alloys
up to 1.0 m/min elting and fusion y trial runs the la
e of powder fus he increase of th g which the lase time results in y the substrate a nt of the structur w scanning rate of craters, wher e may be th ed by inhomogen ix of the alumini nterfusion.
of the silicon car
of the circonium d remelting of t (Figs. 9-12) w n. It has been s n amounts to 0.5 aser power withi sion 0.5 m/min he rate of fusion er beam influenc
limitation of t and as a consequ ral changes. Usin
causes evapora eas using too lo e reason for neous distributio ium cast alloys A
rbide powder (SE
oxide powder ( the surface layer within the rang
tated that the op 5 m/min, therefo in the range 1.5- have been adop causes reduction ces the material the amount of uence leads to lim
ng too high laser ation of the surfa ow power and to inadequate re on of the particle
Al-Si-Cu, or ma EM)
SEM) r of the ge from ptimum ore after -2.0 kW pted for n of the , and at energy mitation r power face and oo high melting es fused ay result
Figcast
Figage
Table
g. 9. Microstruct t state
g. 11. Microstruc eing
e 3. Properties o
D Hard Melti Boilin Radiation r
Thermal Crystallogr
ture of the cast a
cture of the cast
of the ceramic po Properties Density, g/cm3 dness HV, Kg/mm
ng temperature, ng temperature, refraction coeffi transmition, Wm raphic structure,
Colour
aluminium alloy
aluminium alloy
owders used for
m2
°C
°C cient, nD
m-1K-1 unit cell
y AlSi9Cu in as
y AlSi9Cu after
feeding WC 15.69
2400 2870 6000 3.19 84 heksagon
regular black
Fig. 10. Mic as cast state
r Fig. 12. Mic after ageing
nal r
montetr gu w
rostructure of th
crostructure of
ZrO2
5.68 1100
2715 D
4300 2.13 2 nocrlinic ragonal, ularna white
he cast aluminiu
the cast alumin
SiC 3.44 2800 Decomposition in
2700 sublimation
2.55 120 regular
gray
um alloy AlSi9C
nium alloy AlS
Al2O3
3.97 2300
n 2047
2977 1.76 30 trigona
white Cu4 in
i9Cu4
al
