22.6.2005 Pressing & Sintering

Efficient Low-Alloyed Steels for High Performance Structural Applications

The demands on powder metal components for new automotive applications are placing more and more pressure on increased performance at reduced costs. This has created a demand for high performance and cost effective materials that can be used in a variety of applications. The growing interest for chromium as an alloying element for sintered steels is due to the excellent mechanical properties attainable both in the as sintered condition and after heat treatment, such as through hardening or case hardening. Among case hardening treatments, low pressure carburising is an attractive process aimed to improve fatigue strength and wear resistance of PM components.  In this paper properties achievable with a Cr-Mo pre-alloyed powder, Astaloy CrL, after processing by different conditions are described. Properties achieved at different density levels after conventional and high temperature sintering and low pressure carburising are compared. A case study of a production component is also described.