Cost reduction by using new Ni-free PM steels

In order to be prepared for possible end-user's requests to apply high-strength PM parts without processing nickel a consortium consisting of three part producers, a powder manufacturer, a gear-box producer and two research institutes started a BRITE-EuRam project in order to evaluate industrially acceptable nickel-free alloys. The comparative base for the material development was given by the diffusion alloyed PM steel Fe-4.0Ni-1.5Cu-0.5Mo mixed with 0.6C at 7.1 g/cm 3. Among 15 candidate alloy systems the prealloyed material (Fe-3.0Cr-0.5Mo) mixed with 0.5Cu and 0.3C was selected as the most promising one with regard to powder flow, spring-back behaviour, dimensional stability after sintering and mechanical properties. The performance of the new material is verified on the example of three fatigue loaded gear-box components.