Complex Designs in Metal

Metal injection molding (MIM)was a big winner at the 2009 Powder Metallurgy Design Excellence AwardsCompetition, sponsored by the Metal Powder Industries Federation. Two of thefive grand prizes went to MIM parts, while a third received an award ofdistinction.

MIM has a bright outlookbecause of its opportunities to provide complex designs and strong parts. Areport from BCCResearch projects that MIM will grow globally at a 14 percent compoundedannual growth rate over the next five years.

High-Density Air Nozzle

A 316L stainless steelcompressed air nozzle produced by FloMet of Deland, FL, won the handtools/recreation category Grand Prize. The hollow nozzle consists of top andbottom halves that are molded separately and then laser welded together duringdebinding and sintering. Air flow capacity is controlled to comply with U.S. andEuropean Union machine device noise regulations. The complex part has a densityof 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 ahigh-performance fiber-optic module won the Grand Prize in the electrical/electroniccomponents category. The part is a 17-4 PH stainless steel MIM flagstaff noseor EMI nose shield. The part has a density of 7.5 g/cm³, tensilestrength of 130,000 psi, yield strength of 106,000 psi, an eight percentelongation, and a 27 HRC as-sintered hardness. The molder, Advanced MaterialsTechnologies of Singapore, said the intricate one-piece design would have beenalmost impossible to produce by any manufacturing process other than metalinjection molding. Secondary operations are limited to coining on the twolatches and the application of a 0.5 micron gold coating for appearance andcorrosion resistance.

MIM Process Provides Undercuts

Parmatech Corp. of Petaluma, CA,received the Award of Distinction in the hand tools/recreation category for a420 MIM stainless steel housing block used in a 45-caliber handgun. The partcontains a spring mechanism and provides sliding action with other mechanicalparts. It features wings, undercuts, through-holes and blind holes, as well asthin 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.