THE CHEMICAL WORLD THIS WEEK
P o w d e r M e t a l l u r g y Future Held Promising C&EN REPORTS: Stevens Institute Symposium on Powder Metallurgy HOBOKEN, X. J . - O n e of the most promising outlets for engineered parts made by powder metallurgy are those e n tering the manufacture of jet aircraft, stated Paul Schwarzkopf, president, Elec tro Metal Corp., Yonkers, Ν . Υ., at t h e sixth annual medal lecture sponsored b y the Powder Metallurgy Laboratory, Stevens Institute of Technology, here on March 29. These parts will have to stand up under high temperatures a n d high pressures—temperatures of at least 1,560° F.—without suffering undue "creep," which is the metallurgist's term for slow expansion of dimensions. Moreover, these powder metallurgy components must have high resistance to corrosion from hot gases, a high modulus of rigidity, and generally stable qualities. Furthermore, the industry must design new cementing procedures for making such parts. Among the cemented carbides, includ ing those of tungsten, molybdenum, tita nium, cobalt, vanadium, and others, zir conium carbides have the best promise for the future, the speaker stated. Not only is zirconium more a b u n d a n t than
some of the other elements employed, but the qualities of t h e carbide seem superior at this time, although more ex periments will b e needed to verify com pletely this preliminary conclusion. Dr. Schwarzkopf, on the subject of "Mid-Century Review and Preview of Powder Metallurgy," traced t h e history of powder metallurgy, stating that t h e modern art dated from 1903 w h e n t u n g sten a n d molybdenum filaments for elec tric light bulbs were first m a d e by that process. Greatest progress in theory a n d techniques has been m a d e during t h e past 12 months, it was revealed. Products of the early days w e r e pressed merely in bar form b u t today intricate shapes and patterns are being produced. T h e vogue for making cutting tips on machine tools out of cemented carbides began in this country in 1929. However, today these do not differ much from such tools used 20 years ago, particularly in Germany. In fact, t h e Germans used cemented carbides during the first world war, the early use being for making strong, abrasion-resisting dies for drawing wire in the place of diamonds.
for Paint and Lacquer Manufacturers The booklets shown are of special usefulness to paint a n d lacquer man ufacturers as a guide to the use of organic chemicals for new o r im proved products. If you use alcohols, ketones, or glycol-ethersor p r e p a r e emulsions why not get this helpful literature? When writing please address Dept. E-4. "Cellosolve"
and "Carbitol"
Union Carbide
are trade-marks
and Carbon
of
Union Carbide and Carbon Corporation 30:E. 42nd-Street f t m New York 17, N. Y. In C a n a d a : Carbide and/Carbon Chemicals, Umited> Toronto
1290
Monsanto t o Manufacture Molding Compounds in California
Corporation.
CARBIDE AND CARBON CHEMICALS DIVISION
During the second world war the United States employed powder metal lurgy .effectively ,in several lines, the most noted being a certain part in the proximity fuse, "which surpassed all other wartime inventions." T h e speaker pointed out that there arc many applications in which powder meta Iluigy is a " n a t u r a l " and where this m e t h o d of compacting fine metal powders, sintering, pressing, a n d coining makes a product inherently far superior to the same parts and components m a d e b> other techniques. T h e industry is nowstriving to compete with other processes w h e r e t h e need for powder metallurgy items is not so apparent. The greatest handicap is the high cost of the variou.s m e t a l powders, including iron, copper, and brass and bronze powders. However, offsetting the high cost of materials is the elimination of t h e machining opera tion since the parts are shaped to final form in t h e initial process. T h e speaker dwelt on t h e importance of bonds for the metal grains, grain size, and grain shape. H e mentioned the modern use of "infiltration" metals such as silver and copper, particularly the latter, which encase the major metal grains a n d strengthen t h e bonds. He t h r e w diagrams of micrographs of metals on the screen to show the value of this encasement by t h e infiltration metals. Prior to the talk of Dr. Schwarzkopf, he was a w a r d e d the annual Stevens In stitute medal for the best contribution to powder metallurgy. T h e presentation was m a d e by Harvey N. Davis, president of the institute. Dr. Schwarzkopf has been a pioneer for 30 years in the powder metallurgy field. Among his accomplish ments w e r e t h e development of Elmet metal, a heavy-duty material for electrical contacts, and Cutanit, a steel-cutting nuilticarbide tool that increases cutting efficiency 16 times. W h e n introducing t h e speaker it was pointed out t h a t Dr. Schwarzkopf h a d practiced his profession in several countries and h a d learned of progress in his field first-hand from many quarters.
AUOHCHS
*-4?*l
KÈTQHIS
F-474;
" « U o s o i v f ANS "CAs&irov *tuyE«rs fAm *ttpLS4
