Structure and Properties of Open--Cell 316L Stainless Steel Foams Produced by a Powder Metallurgy-Based Process

摘要

This paper presents the structure and properties of stainless steel foams produced using a powder metallurgy approach. Stainless steel powders, a polymeric binder and a chemical foaming agent were dry blended together. The resulting powder was molded and heat-treated to foam, debind and sinter the particles. During the foaming step, the binder melts and flows around the particles. Once the binder is melted, the foaming agent starts to decompose and generates a gas which expands the material. After the foaming step, the material is a polymer foam charged with the stainless steel particles. The material is then treated at higher temperatures to decompose the polymer and finally to consolidate the metallic particles by sintering. The density, porosity and morphology of the stainless steel foams were studied at different stages of the production process. The mechanical properties of foams were also evaluated in compression after sintering. The resulting material has open and closed pores, and could be used in structural applications.