Heat Treatment, Microstructure, Hardness and Corrosion Resistance of Martensitic Stainless Steel X65Cr13 (1.4037)

Abstract

The corrosion resistance of martensitic stainless steels is influenced by the alloy composition and the heat treatment. It is known that the proportion of chromium carbides in the microstructure and the resulting hardness are influenced by the heat treatment (austenitization temperature and duration, cooling rate, deep freezing, tempering temperature). The connection between carbon content, the exact heat treatment parameters and corrosion resistance of martensitic stainless steels with 13 wt.% chromium is only known for lower carbon contents (X20Cr13, X46Cr13). This paper is therefore dedicated to the steel X65Cr13, which is used in particular for razor blades. Materials research results are presented that show the influence of hardening on microstructure, hardness and corrosion resistance. It is shown that the steel X65Cr13 has only limited corrosion resistance due to its high carbon content, which can be attributed to the presence of chromium carbides and local chromium depletion in the microstructure. It is also clear that higher austenitizing temperatures and durations as well as high cooling rates lead to an improvement in corrosion resistance. However, this approach also causes retained austenite, which still has to be converted into martensite by deep freezing after quenching.