Abstract:

Martensitic stainless steels are distinguished from other stainless steels by their good mechanical properties and moderate corrosion resistance. The need for superior properties in certain applications has led to extensive research into improving the performance of these steels. For this, it is recommended that the heat treatment parameters be determined correctly. In this study, it has been revealed that the austenitization temperature of AISI 440B martensitic stainless steel has a significant effect on wear and corrosion resistance. As the austenitization temperature increases, Cr23C6 carbides dissolve and C and Cr enrichment occur in the austenite matrix. While Cr enrichment improves corrosion resistance, C enrichment increases material hardness. However, at high austenitizing temperatures, the amount of residual austenite increases due to the decrease of Mf. Since austenite grain coarsening also occurs, a significant decrease in hardness occurs. On the other hand, due to the high carbon content, distortions occur in the crystal lattice of the martensite phase, which negatively affects the stability of the protective oxide film and reduces the corrosion resistance. In this study, the optimum austenitization temperature was determined as 1080°C to obtain the best wear and corrosion resistance.

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