The Effect of Cryogenic Treatment and Tempering Duration on the Microstructure and Mechanical Properties of Martensitic Stainless Steel 13Cr-2Ni-2Mo
Journal
Materials
Journal Volume
18
Journal Issue
8
Start Page
1784
ISSN
1996-1944
Date Issued
2025-04
Author(s)
Abstract
Martensitic stainless steel (MSS) is widely used in several parts of automobiles where high strength, hardness, and corrosion resistance are required. However, the metastability of retained austenite can transform into martensite under severe deformation, adversely affecting material properties. Cryogenic treatments (CTs) have been extensively employed in iron-based alloys for fastener application due to their advantageous effect. This study explores the heat treatment processes applied to 13Cr-2Ni-2Mo martensitic stainless steel (MSS), including austenitizing, cryogenic treatment, and tempering cycles. Cryogenic treatment at (−150 °C) for varying durations, followed by tempering at 200 °C for 2 h, and the impact of post-cryogenic tempering at 200 °C for different tempering duration on the microstructure and mechanical properties were evaluated. Experimental results indicate that the sample quenched at 1040 °C for 2 h (CHT) contains lath martensite, retained austenite, δ-ferrite, and undissolved carbide precipitation. Compared to as-quenched samples, hardness decreased by 5.04%, 7.24%, and 7.32% after tempering for 2 h, 5 h, and 10 h, respectively. Extending cryogenic durations to 2 h, 12 h, and 20 h promoted nucleation of a mixture of M3C and M23C6 small globular carbides (SGCs) and grain refinement but resulted in hardness reductions of 5.04%, 5.32%, and 8.36%, respectively. The reduction in hardness is primarily attributed to a decrease in solid solution strengthening and promoted carbide coarsening.
Subjects
cryogenic treatment
martensitic stainless steel
mechanical properties
microstructure
retained austenite
Publisher
MDPI AG
Type
journal article