Word: powderly
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...powder metallurgy's products are often much cheaper than those of fusion metal particularly for small complicated shapes like gears. They look just like ordinary metal to the naked eye; they can ultimately be made equally strong. But they have distinct advantages, chiefly 1) light weight, 2) porosity which enables them to absorb large quantities of oil, giving them semi-permanent built-in lubrication...
...told, some 5,000 tons of metallic powder will be used in metallurgy this year-up 25% over 1940, 100% over 1936. Students returning this fall to several engineering colleges-Michigan, Minnesota, Ohio State, others-found a new department had been added to teach them powder tricks which many an oldtime engineer wished he knew. So fast has powder metallurgy expanded in industry that shop practice has sometimes outstripped basic theory. Leading U.S. academic metal powder laboratory is directed by Gregory Jamieson Comstock at Stevens Institute of Technology...
...individual dustlike particles in a cubic centimeter of metal powder may have a total surface of approximately 384,000 square centimeters, making a tremendous amount of surface energy available ; but even so the cold-pressed briquets are not very strong and can be easily broken by hand unless they are strengthened by sintering-consolidating heat treatment by baking at temperatures well below their melting points. This heat also shrinks the pressed part, in some cases very little, in others 20%. Yet in each metal the shrinkage is controllable enough so that parts can be made precise to within...
Platinum & Diamond Dust. A pioneer of powder metallurgy was an Englishman, William Hyde Wollaston, who in 1829 described a process for working platinum, whose melting point (3224° F.) was too high for the crude furnaces then in use. As better furnaces were developed, his technique was little used until about 1910 when U.S. scientists, notably General Electric's William David Coolidge, revived it as the only practical way of making ductile tungsten (melting point 6100° F.) from which thin wires for light bulb filaments could then be drawn through holes in diamonds...
...Jacques Daguerre had just astonished the world by making the first photographs on chemically treated plates. In Manhattan Samuel F. B. Morse, who had just invented the telegraph, was busy on the roof of New York University making new-fangled "sun pictures." Morse's models, faces whitened with powder, had to sit immobile for half an hour in the sunlight, before their likenesses registered in his primitive camera...