Pre-Alloyed Chromium Materials for Highly Fatigue Loaded PM Parts
PM²TEC 2004, in Chicago, USA. Authors: Anders Bergmark, Ola Bergman, Luigi Alzati. The use of PM materials in highly loaded components is continuously expanding. Fatigue properties on such parts are becoming more and more important. Pre-alloyed chromium materials enables cost efficient productions of highly fatigue loaded PM parts. In this paper fatigue performance of pre-alloyed chromium material sintered at 1120 °C(2050°F), 1250 °C(2280 °F) and 1280 °C(2340 °F) are presented. Cold compaction to 7.0 – 7.1 g/cm³ and warm compaction to 7.3 g/cm³ are used. The materials are processed to high performance microstructures obtained directly in as sintered state after normal cooling. Shot peening has been shown to be a very efficient process route on Chromium pre-alloyed materials with fine pearlite or tempered martensite microstructures. The results of the Chromium pre-alloyed materials are compared to diffusion alloyed high performance material D.HP1. Dynamic data are presented and correlations between microstructures and mechanical properties are stated.