“Although achievement of carbide’s full potentialities as a design material plates, sleeves, bushings and bearings, and a large variety of parts of specialized design. Prime reason for its popularity is the decline in cost of carbide metal resulting from increased production.
“Already, carbides are proving effec
tive in minimizing wear even under ex
treme conditions. Typical examples are the application of carbide liners to brick molds and molds used in powder metal
lurgy; grinder parts for the fine grinding of paint pigments and other abrasive materials; guide rings in wire stranding machines; etc. Of tremendous impor
tance is the experimental work now be
ing conducted with carbide as a bear
ing material—both for sleeve type and ball bearings. In some instances, a car
bide shaft has been run in a carbide journal with truly astonishing results.
“Carbides are being found equally economical where only mild conditions of wear exist, such as in the manufacture of ‘Jo’ blocks; indicator points; meter fingers and lathe and grinder centers.
Frequently, parts exposed to wear—
whether conditions be extreme or mild—
are subjected simultaneously to other conditions which tend to accelerate wear.
Here, the combination of uniformly high hardness, strength, and great resistance to various types of wear of carbide met
al together with its generally good re
sistance to certain forms of erosion and corrosion, has served to materially pro
long the life of equipment when used in the form of valve seats; nozzles for spray painting, etc.
“Economies which can be generally
realized by incorporating carbides into product design cannot be evaluated easily at this stage of its utilization. various complicated shapes, mostly for direct current applications.
“Pole pieces with one or more curved faces and rotors with several step-like projections have been manufactured from pure carbon-free iron powders in pro product. A high-temperature sintering operation consolidates the porous struc
ture and makes the metal sufficiently ductile to yield under high pressure in a coining operation, whose purpose is to form a substantially dense part in its final shape.
“The extremely strain hardened struc
ture, which in some cases has under
gone a cold reduction of 2:1, is advan
tageously recovered by a low tempera
ture hydrogen annealing treatment. For optimum magnetic permeability and min
imum eddy current losses, annealing is combined with a second high tempera
ture sintering.
“The industrial development of this process, w’hich, except for a few minor finishing operations, does away with all machining, thus saving tons of scrap metal and untold manhours, has required
most modern equipment for pressing and sintering. While the new sintering fur
naces used in this process provide an ex
tremely pure atmosphere which is neutral against carbon, the molding of some of these parts has been accomplished with new quick acting presses providing com
plicated motions for a variety of simul
taneously moving punches.”
Price of M etal Pow ders U sed in Electronics Field No Object
H
C h a r l e s H a r d y , new applications found for this comparatively new art. Not all applications
ticularly in the electrical field—in elec
tronics, X-rays, radio, radar, etc.
“The large consumption of metal pow
ders is still in the field of bushings and bearings, or perhaps better expressed in antifriction and friction-material produc
tion. Machine parts made from com
binations of various elements where pro
duction can be speeded up and man- hours saved probably comes next in line of importance.
“The number of applications which heretofore were classified as ‘can’t be done’ is getting smaller and smaller.
“Nineteen hundred and forty-five should, based upon the research and development work done in 1944, show further growth of this industry.”
Diffusion A lloying of Powders
ter physical properties. Alloy powders which have been hard to fabricate are be
ing developed with characteristics which makes the pressing easier. Other alloy powders that are available in production quantities are in the experimental stage.
“Better presses and better powders are leading to better physical properties and a committee has been formed to specify properties have become commonplace.
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M A C H I N I N G
striking developments, however, are still‘in work’ and will not be announced importance when attempting to reach these objectives. pressure and ultimately escapes, par
tially through an exhaust port and partially through the bearing enclosures.
“The result is perfect bearing lub effect, the low operating temperature achieved is attributed more to the very minute quantity of oil which is used.
“This means of lubrication is also being applied to high-speed gearboxes with equally favorable results.”
M achining at 20,000 F eet Per Minute Done in Hypermilling Malcolm F. Judkins, chief engineer, Firthite Division, Firth-Sterling Steel Co., McKeesport, Pa.: “The news about and metalworking machines. Equipment and mechanisms are never wrought into final form direct from castings, forgings, stampings or drawings. Every minute piece down to miniscule gears for air
craft instruments must feel the magic touch of the toolmaker and the machin
ist. Neither accuracy nor precision are ever accidents. Efficient, smoothly run
ning mechanisms represent hours of careful machining.
“Sintered carbides are the indispens
able ingredient in the formula for suc
cessful warfare because tools tipped with them:
1—Cut faster 2—Last longer
3—Remove metal most rapidly—up to 1000 pounds per hour
4—Multiply the productivity of work
ers and machines
5—Conserve vitally strategic materials by reducing scrap
“The most outstanding achievements of sintered carbide tipped tools are in the field of hypermilling. Breech blocks and rings for cannon as well as gun mounts required long hours of milling by the older methods. Hours become minutes through the supcrspeeds em
ployed in hypermilling. Feeds (rate of work travel past the cutter) range up to
40 inches per minute even on hardened steel. Heat treated, high-strength (highly alloyed) steel parts for retractable air
craft landing gear are speedily finish milled to close limits by the hypermilling method. Heat treated aluminum alloy cap spars (wing cantilever beam mem
bers) are machined by the hypermilling technique at speeds exceeding 20,000 feet per minute and feeds up to 240
M achine Eliminates Separate O peration for Pointing Bolts
C. N. K irk p a tric k ,
duction of war components. Cutting tools played an equally important part. Ma
chine tools for the postwar period will embody many new features in design which will result in increased efficiency, improved production, and what is more important, in lower manufacturing costs.
Again cutting tools will play an equal offer an automatic combination rolling and pointing machine. There has never been such a machine placed upon the market before. It will eliminate a sep
arate operation for pointing bolts, screws, studs, etc., and operation will cost practically nothing. Other new machines also are being prepared.
“New Landis die heads, collapsible taps and a distinctive design of chaser will also be offered in the postwar period.
Extensive experimental and development work along metallurgical lines have al
ready resulted in long tool life and higher cutting speeds.
“Generally, machine tools and cutting tools will be manufactured having in mind the great importance of reducing manufacturing costs. During the war period, costs have been given very little
ANNOUNCING
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