15.5.2001 Pressing & Sintering

Rolling Contact Fatigue Tests of Selectively Densified Materials

PM² TEC 2001, in New Orleans, USA. Authors: Sven Bengtsson, Linnéa Fordén. The fatigue behaviour of a powder metallurgy component depends strongly on its density. By using selective densification, the local density can be improved to near full density. This procedure is well suited for components with a high stress near the surface. Rolling contact fatigue experiments have been conducted on selectively densified materials. The rolling contact fatigue endurance limit of the Astaloy Mo based material is approximately 1500 MPa that can be compared to the selected reference material, AISI 5115 (DIN 16MnCr5), 1600 MPa. For the diffusion alloyed material, D.DC-1, it was not possible to determine the endurance limit due to too few tests. However, the endurance limit is believed to be slightly lower than the Astaloy Mo material. The case depth is believed to be to low for both materials, but the effect to be more severe for the D.DC-1 material.