09.6.2008 Pressing & Sintering

Properties of 17-4 PH Stainless Steel Produced via Press and Sinter Route

Ferritic and austenitic stainless steels exhibit moderate levels of strength which are adequate for a wide range of applications. Martensitic stainless steels offer significantly higher strengths, but have very low ductility. For applications requiring high levels of strength (typically, above 600 MPa, 87 KSI in tensile strength) and a moderate ductility, alloys from the precipitation strengthened family of stainless steels are often considered as potential candidates. The most popular alloy of this family is 17-4 PH. Full dense version of this alloy, produced via MIM route, has gained a high degree of acceptance in many demanding applications.  Conventional PM processing of 17-4 PH poses a number of challenges, the primary one being the achievement of a near-full theoretical density. This paper describes the optimum processing parameters, and properties of the alloy in both as-sintered and heat treated conditions. The effects of process parameters and the residual carbon content on the microstructure and mechanical properties are examined.