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The as-sintered and the sintered and tempered transverse rupture and tensile properties of seven recently developed high performance PM compositions are reviewed. Two are improved versions of the well known diffusion alloyed grades according to MPIF Standard 35. Two others are likewise improved versions of more highly alloyed analogs of the latter that have only recently been introduced. The remaining three are all new compositions that take advantage of the powerful alloying effects of silicon. The silicon is added by a proprietary method that greatly reduces its susceptibility to oxidation during sintering, an effect that has heretofore limited its use.

Malleable and ductile cast irons are used extensively in automotive applications such as clutches, gears, carriers, shafts, bearings, cam, racers, hubs, etc. Recently developed P/M materials can be processed cost efficiently to replace malleable and ductile iron castings. An UTS in excess of 1240 MPa and a YS in excess of 825 MPa can be achieved with one of these new materials. These tensile properties can be coupled with elongations over 2% and impact energies over 25 Joules. This presentation will cover processing routes for these new materials and will identify parts that may benefit from this new technological advancement.

The advent of stainless steel automotive exhaust systems presents a significant opportunity for powder metallurgy (P/M) parts and the inherent economic advantages of this near net shape metalworking technology. A study was performed to determine the viability of ferritic P/M stainless steel parts for exhaust applications such as coupling flanges and hot exhaust gas oxygen sensor (HEGOS) bosses. In order to help achieve the automotive industry's stated goal of extending the functional life of exhaust components while remaining competitive, the authors developed a program to develop a database of the mechanical properties and performance characteristics of several grades of P/M stainless steel. Among the data generated and analyzed for these ferritic alloy systems are room temperature, tensile stress-strain curves, fatigue and endurance properties, hardness levels, and corrosion resistance.