Winners of the 2009 Powder Metallurgy Design Excellence Awards Competition, sponsored by the Metal Powder Industries Federation (MPIF).
Receiving grand prizes and awards of distinction, the winning parts are outstanding examples of powder metallurgy’s (PM) precision, performance, complexity, economy, and innovative design advantages.
The Grand Prize in the automotive-engine category was given to Capstan, Inc., Carson, California and its customer Jacobs Vehicle Systems, a division of Danaher, for a PM steel manifold assembled with a solenoid into the valve train of a heavy-duty diesel I-6 truck engine (Fig. 1). The part assists with the activation of the ‘Jake Brake’ system inside the engine cylinder head during the exhaust cycle, reducing horsepower and performing a braking action to slow the vehicle. Made to a minimum density of 6.7 g/cm3, the manifold has a minimum yield strength (YS) of 345MPa (50,000psi) and an ultimate tensile strength (UTS) of 415MPa (60,000psi). Its complex design features include the variation in thickness levels and cylindrical radius. Secondary operations include machining the solenoid bore and two port holes. The PM process provided an estimated 20% cost reduction over the alternative casting process.
ASCO Sintering Co., of Commerce, California, received the Grand Prize Award in the hardware/appliances category for a lockset retractor assembly (Fig. 2) made for Best Access Systems–Stanley Security Solutions. The assembly functions as the heart of the mechanism in a heavy-duty door lockset system. Its ‘3D puzzle’ design of two identical halves not only satisfied various functional force-transfer modes and geometry requirements, but allowed ASCO to partner with equipment suppliers to develop a pick-and-place ‘green’ stage assembly from two consecutive parts that allowed the customer to remove an entire riveting sub-assembly line at an annual cost saving of $250,000. The ‘single jaw’ design easily withstands the required 500 lb force load and a 100 lb axial pull. Made to a net shape, the assembly has a density of 6.7g/cm3, 415MPa (60,000psi) UTS, transverse rupture strength of 860 MPa (125,000psi) and a fatigue limit of 158 MPa (23,000psi).
FMS Corp., of Minneapolis, Minnesota and its customer Team Industries received the Grand Prize in this category for an assembly of five complex PM steel parts (two shift forks, two sector gears and a park pawl (Fig. 3) that go into an all-terrain vehicle transmission. The sector gears have AGMA Class 6 splines. Four of the parts are made from PM sinter-hardened steel to a density of 7.2g/cm3 and have a minimum UTS of 760MPa (110,000psi). One sector gear, a net shape, is made from 4300 steel and has a UTS of 1100 MPa (160,000psi) and 30 HRC minimum hardness. The other parts require only minimal machining. The customer saved an estimated 60% by choosing PM over machined parts.
MIM producer FloMet LLC of Deland, Florida, won Grand Prize in this category for a 316L stainless steel compressed air nozzle (Fig. 4) made for Silvent AB, Borås, Sweden. The hollow MIM nozzle consists of top and bottom halves that are moulded separately and then joined together into one piece during debinding and sintering. The nozzle’s air flow capacity is tightly controlled to ensure optimum use of compressed air as well as to comply with U.S. and European Union machine device noise regulations. It can withstand high ambient temperatures, corrosive environments and meets hygienic requirements of the food processing industry. The complex part has a density of more than 7.6g/cm3, an UTS of 517 MPa (75,000psi), yield strength of 172 MPa (25,000psi) and a 50% elongation. After sintering, the seams where the two sections join together are laser welded for a leak-free seal.
Another MIM producer, Advanced Materials Technologies Pte Ltd. of Singapore, received the Grand Prize in this category for a 17-4 PH stainless steel MIM flagstaff nose or EMI nose shield (Fig. 5) , which serves as an external connector for a high-performance fibre-optic module. The part has a density of 7.5g/cm3, UTS of 896 MPa (130,000 psi), YS of 730MPa (106,000psi) , an 8% elongation and 27 HRC as-sintered hardness. The intricate one-piece design would have been almost impossible to produce by any manufacturing process other than metal injection moulding. 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. Specifying MIM gave the customer an estimated 40% cost saving.
Awards of Distinction
PMG Indiana Corporation, Columbus, Indiana, won the Award of Distinction in the automotive engine category for three high-precision PM steel parts (Fig. 6), a slide, housing and rotor, which operate in oil pumps in new larger hybrid SUVs. Choosing PM improved the oil pump’s efficiency in addition to reducing energy consumption and lowering vibration. The variable-displacement vane pump delivers oil when needed on demand, eliminating unnecessary oil flow. All three parts are made to a net shape and only require double-disk grinding for maintaining thickness and flatness tolerances. The parts have a density range of 6.5 g/cm3 for the housing, 6.6 g/cm3 for the slide and 6.8 g/cm3 for the rotor. They are made on an automated compacting–sintering–sizing flow line because of their complexity and fragility.
Porite Taiwan Co. Ltd., Taiwan, won the Award of Distinction in the hardware/appliances category for a copper-infiltrated PM steel weight balance (Fig. 7) used in a new compact compressor and manufactured for Taiwan Hitachi Co. Ltd., Taiwan. Made to a density of more than 7.2g/cm3, the multi-level part has a tensile strength of 87,000 psi, yield strength of 60,000 psi and an 80–85HRB hardness range. The complicated final shape was achieved by additional machining. Choosing PM over casting or machining provided a cost saving of more than 70%.
Parmatech Corporation, Petaluma, California, received the Award of Distinction in the hand tools/recreation category for a 420 MIM stainless steel housing block (Fig. 8) used in a 45-caliber handgun. It contains the firearm’s spring mechanism and provides sliding action with other mechanical parts. The complex MIM part features wings, undercuts, through-holes and blind holes, as well as thin and thick cross sections. Formed to a final density of 7.7g/cm3, the part has a tensile strength of 261,000psi, yield strength of 218,000psi and a 48–52HRC hardness range. Choosing the MIM process offers a very significant savings over machining.
Megamet Solid Metals Inc., Earth City, Missouri, received the Award of Distinction in the aerospace/military category for a handle body and yoke (Fig. 9) made by the MIM process for its customer, Colt Canada Corp., Kitchener, Ontario, Canada. Made from 4140 low-alloy steel to a density of 7.4g/cm3, the parts are core components in a folding-front-grip assembly that attaches to the Picatinny Rail system used on modern military rifles. Challenges presented by the geometric complexity of the parts are efficiently and cost-effectively solved by the MIM process. The parts are sintered in a nitrogen atmosphere followed by post-sintering operations that include coining, reaming and tapping. The components are quenched and tempered to a 45-50 Rockwell C hardness range. Parts are supplied to the customer with a manganese phosphate finish.
More information: www.mpif.org