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The usage of powder metallurgy in automotive electromagnetic applications has increased dramatically. The combination of P/M's unique shaping making capability, the efficiencies of the process and the design flexibility of the materials have opened significant growth opportunity. Magnetic applications via P/M need not be limited to DC applications; the recent development on non-sintered P/M materials permits their usage in AC applications. This paper will document the current uses of P/M in both DC and AC applications.

Model testing for rolling contact fatigue (RCF) strength is an important tool for pre-selecting materials and processes for highly loaded gear applications. S-N curves based upon final and catastrophic failure are used to compare material compositions and effects of process parameters in order to improve life time until fracture. The introduction of eddy current technology to detect cracks in the very early stages of nucleation is about to change failure definition in RCF and allows a completely new approach to understanding initiation and propagation of flaws and failures in RCF. This paper describes the fundamental principle of eddy current technology in RCF testing and presents first results on wrought and PM steels. It also contains first test results on crack propagation at different levels of contact pressure, even below the “endurance” limit. The practical consequences of the new approach will be discussed, as well as the impact on future model testing procedures.

Machinability of powder metal components (P/M) requires a better understanding material compositon, microstructure, and machining process conditions. By employing the appropriate machinability additives and base powder design, machining productivity can be optimized. Through proper application planning, the material supplier, P/M fabricator, and end user can design the P/M system to balance part performance and machinability requirements.