PIM Powders and Feedstocks
|Smaller, less expensive powders developed |
Water-atomized powders are less expensive than more spherical gas-atomized powders. However, they have a coarser, more irregular shape and a higher oxygen content. Though conventional wisdom says that water-atomized powders can decrease part deformation during debinding and sintering, it also says that these same powders undergo a higher degree of shrinkage. Therefore, part dimensional accuracy may be inferior when using them instead of gas-atomized powders.
Atmix, formerly known as Pacific Metals, uses unconventional ultrafine technology to combine gas and water atomization (see June 1999 IMMC, p. 32). Its latest market entry on this front is its R-type Series, designed to approximate the benefits of gas-atomized powders, while still holding the line on cost.
Compared to its previously released powders, R-type powders reportedly can reduce binder volume by 40 percent and shrinkage by nearly 50 percent. Oxygen content also has been nearly cut in half.
Atmix representative United States Bronze Powders adds that the company has even more recently developed a pure nickel 2-µm powder for micromolding.
United States Bronze Powders Inc.
Pilot plant launched
Ultrafine PIM powders
Hoeganaes Corp., Cinnaminson, NJ
New feedstock supplier
Apex Advanced Technologies LLC
|Creep-resistant alloy |
A new alloy from Noranda, designated AE42, is said to exhibit better creep resistance at high temperatures than AZ91D, even though it processes at somewhat higher temperatures. In addition to better creep resistance, it also has good vibration-absorbing characteristics and stiffness, suiting it to lightweight automotive applications in power trains.
Still in the experimental phase, another alloy from the company touted for its creep resistance is magnesium-aluminum-strontium, available in high- and low-strontium grades. The alloys reportedly exhibit excellent high-temperature creep strength and bolt-load retention, and have a corrosion rate comparable to existing high-purity magnesium alloys.
Noranda Magnesium Inc.
TXM chips are shaping up
Rossborough Mfg. Co.