Metal injection molding (MIM) was a big winner at the 2009 Powder Metallurgy Design Excellence Awards Competition, sponsored by the Metal Powder Industries Federation. Two of the five grand prizes went to MIM parts, while a third received an award of distinction.
MIM has a bright outlook because of its opportunities to provide complex designs and strong parts. A report from BCC Research projects that MIM will grow globally at a 14 percent compounded annual growth rate over the next five years.
High-Density Air Nozzle
A 316L stainless steel compressed air nozzle produced by FloMet of Deland, FL, won the hand tools/recreation category Grand Prize. The hollow nozzle consists of top and bottom halves that are molded separately and then laser welded together during debinding and sintering. Air flow capacity is controlled to comply with U.S. and European Union machine device noise regulations. The complex part has a density of more than 7.6 g/cm3, an ultimate tensile strength of 75,000 psi, yield strength of 25,000 psi and a 50 percent elongation.
Intricate One-Piece Design
An external connector for a high-performance fiber-optic module won the Grand Prize in the electrical/electronic components category. The part is a 17-4 PH stainless steel MIM flagstaff nose or EMI nose shield. The part has a density of 7.5 g/cm3, tensile strength of 130,000 psi, yield strength of 106,000 psi, an eight percent elongation, and a 27 HRC as-sintered hardness. The molder, Advanced Materials Technologies of Singapore, said the intricate one-piece design would have been almost impossible to produce by any manufacturing process other than metal injection molding. Secondary operations are limited to coining on the two latches and the application of a 0.5 micron gold coating for appearance and corrosion resistance.
MIM Process Provides Undercuts
Parmatech Corp. of Petaluma, CA, received the Award of Distinction in the hand tools/recreation category for a 420 MIM stainless steel housing block used in a 45-caliber handgun. The part contains a spring mechanism and provides sliding action with other mechanical parts. It features wings, undercuts, through-holes and blind holes, as well as thin and thick cross sections. Formed to a final density of 7.7 g/cm3, the part has a tensile strength of 261,000 psi, yield strength of 218,000 psi, and a 48-52 HRC hardness range.