NEW WATER-ATOMIZED TEMPERING STEEL POWDER FOR HIGH-STRENGTH AND WEAR-RESISTANT SINTERED STEELS IN THE AUTOMOTIVE INDUSTRY

The strength properties of new sintered steels are compared with those of cast materials and compact steels, and the future development goals outlined. The prealloyed Mannesmann heat-treatable steel powder MSP 4 (Fe-4.0 Ni-0.5 Mo) for, e.g., synchronizer bodies, clutch hubs and starter pinions, as well as MSP-1.5 Mo (Fe-1.5 Mo) for, e.g., sintered cams and sintered connecting rods, have performed satisfactorily in initial test runs for wear-resistant and highly dynamically loaded automotive components. The diffusion alloyed grades Ultrapac (L)-10/20 Cu were successfully tested as newly developed materials for obtaining a defined copper content in PM components, by means of which undesired copper segregation is substantially reduced. The consequence is a distinct narrowing of dimensional scatter in sintered parts and a considerable improvement in concentricity.