Powder Metal Designs Win PowderMet 2009 Awards

A steel manifold, lockset refractor, all-terrain-vehicle transmission parts, an air nozzle, and a fiber-optic connector all garnered honors in the 2009 Powder Metallurgy Design Excellence Awards Competition. The competition, sponsored by the Metal Powder Industries Federation (MPIF), covered five categories: automotive engines, hardware and appliances, lawn and garden and off-highway, hand tool and recreation, and electrical and electronic components. There were also awards of distinction in the automotive engines, hardware and appliances, hand tool and recreation, and aerospace and military categories.

PM engine power
The automotive-engine grand prize went to a powdered-metal (PM) steel manifold developed by Capstan Inc., Carson, Calif., and Capstan’s customer Jacobs Vehicle Systems, a division of Danaher, Bloomfield, Conn. The manifold, assembled with a solenoid into the valve-train of a heavy-duty diesel I-6 truck engine, helps activate the vehicle’s engine or “jake” brake. The part sits inside cylinder heads and reduces horsepower during the valves’ exhaust cycle, thus slowing the vehicle.

PM molding permitted thickness variations, a cylindrical radius, and a minimum density of 6.7 gm/cm3. To withstand the temperature and pressures inside the cylinder head, the manifold’s minimum yield strength is 50 ksi with an ultimate tensile strength of 60 ksi. Jacobs estimates the PM part, including machining a bore for the solenoid and two port holes, cost 20% less than casting.

Three high-precision PM steel parts made by PMG Indiana Corp., Columbus, Ind., won the Award of Distinction in the automotive engine category. The slide, rotor, and housing operate in oil pumps used in the newest generation of large hybrid SUVs. The pumps save energy usually wasted by unnecessary oil flow by delivering oil only on demand.

The slide’s density is 6.6 gm/cm3, the rotor’s is 6.8 gm/cm3, and the housing’s is 6.5 gm/cm3. All three components are made to net shape and double-disk ground to meet thickness and flatness tolerances.

Sintered hardware
A lockset retractor made by Asco Sintering Co., Commerce, Calif., for Best Access Systems – Stanley Security Solutions, Indianapolis, won the grand prize in the hardware and appliances category. The retractor, part of a heavy-duty door lock, withstands 500 lb of axial load and a 100 lb axial pull. Its density is 6.7 gm /cm³ and it has a 60-ksi tensile strength, 125-ksi transverse rupture strength, and a 23- ksi fatigue limit. The retractor’s design was coupled with a pick-and-place “green” stage assembly process that eliminates a riveting step and saves approximately $250,000/year.

The Award of Distinction in this category went to a copper-infiltrated, PM-steel weight balance made by Porite Taiwan Co. LLC for Taiwan Hitachi Co. Ltd., both of Taiwan. The multilevel part goes into a compact compressor. Powdered metal compressed to over 7.2 gm/cm³ provides a tensile strength of 87 ksi and a yield strength of 60 ksi. Hardness is 80 to 85 HRB.

A secondary machining operation gives the balance its complicated final shape. Taiwan Hitachi estimates the PM part is 70% less expensive than if it were cast.

On target with off-highway
An assembly of five complex PM steel parts won the grand prize in the off-highway category. The two shift forks, two sector gears, and a park pawl that go into an all-terrain- vehicle transmission were made by FMS Corp., Minneapolis, for its customer Team Industries, Bagley, Minn.

Both shift forks, one gear, and the pawl are from sinter-hardened PM steel to a density of 7.2 gm/cm³ and an ultimate tensile strength of 110 ksi. The other sector gear is 4300 steel with a tensile strength of 160 ksi and a minimum hardness of 30 HRC. Both gears have AGMA Class 6 splines.

The 4300-steel gear is made to net shape while the other four parts need minimal machining. The customer estimates a 60% savings over machined parts.

Heavy-duty hand tools
The grand prize in the hand tool and recreation category went to a 316L stainless-steel air nozzle manufactured by Silvent AB, Boras, Sweden. The part is made using metal-injection-molded top and bottom halves that are joined during the debinding and sintering process. The two sections are laser welded together for a leak-free seal.

The nozzle ensures optimal use of compressed air and complies with U.S. and E.U. noise regulations. The 316L alloy resists high temperatures and corrosive chemicals and meets food-industry hygiene requirements. The part’s density is 7.6 gm/cm³. Its ultimate tensile strength is 75 ksi, and its yield strength is 25 ksi with 50% elongation.

A stainless-steel housing block for a .45-caliber handgun earned the Award of Distinction in this category. The part, made by Parmatech Corp., Pentaluma, Calif., is made by metal injection molding 420 stainless steel. It contains the firearm’s spring mechanism and slides against other mechanical parts.

MIM let the wings, undercuts, through-holes, blind holes, and variable-thickness cross sections be molded into the part. The part has a 7.7-gm/cm³ density, a 261-ksi tensile strength, a 218-ksi yield strength, and 48 to 52 HRC hardness.

Electrifying design
A 17-4 precipitation-hardening stainless-steel EMI nose shield won the grand prize in the electrical and electronic components category. The part, made by Advanced Materials Technologies Pte Ltd., Singapore, is an external connector for a fiber-optic module.

The part’ density is 7.5-gm/cm³, and it boasts a 130-ksi tensile strength, 106-ksi yield strength, and 8% elongation. The 27-HRC part is formed in one piece using MIM. Two latches are coined in a secondary operation, and a 0.5- m gold coating is applied for aesthetics and corrosion resistance.

The company says its customers saves about 40% using MIM.

Military metals
An award of distinction went to parts Megamet Solid Metals Inc., Earth City, Mo., made for Colt Canada Corp.’s (Kitchener, Ont.) folding front grip for military rifles. The handle body and yoke are both geometrically complex, but MIM let the 4140 low-alloy steel reach a density of 7.4 gm/cm³.

After nitrogen-atmosphere sintering, the parts are coined, reamed, and tapped before being quenched and tempered to 45 to 50 HRC and coated with a manganese phosphate finish.