Xu Lei,Qie Mofan,Pu Yanhao,et al.Effect of Heat Treatment Regime on Mechanical Properties and Microstructure of 0.37C-0.6Mn-0.82Cr Steel[J].Special Steel,2026,47(01):106-111.
Xu Lei,Qie Mofan,Pu Yanhao,et al.Effect of Heat Treatment Regime on Mechanical Properties and Microstructure of 0.37C-0.6Mn-0.82Cr Steel[J].Special Steel,2026,47(01):106-111. DOI: 10.20057/j.1003-8620.2025-00086.
Effect of Heat Treatment Regime on Mechanical Properties and Microstructure of 0.37C-0.6Mn-0.82Cr Steel
This study investigated a 0.37C-0.6Mn-0.82Cr steel fabricated through a processing route consisting of homogenization heat treatment, cold rolling, and intercritical heat treatment. The effects of different heat treatment regimes on the mechanical properties and microstructure evolution of 0.37C-0.6Mn-0.82Cr steel were systematically analyzed. The results indicated that annealing treatment involving furnace cooling from 840 ℃ to 800 ℃ followed by air cooling produced a ferrite-martensite dual-phase steel with superior mechanical properties, a hardness of 298.7 HV, ultimate tensile strength of 928 MPa, yield strength of 858 MPa, and elongation of 17.8%. The enhanced performance was attributed to the refinement of martensitic structure during cold rolling. Subsequent intercritical annealing at 840 ℃-800 ℃ induced static recovery and recrystallization of the refined martensite. Quantitative microstructure characterization revealed that fine grain size is around 1 μ m, and the coarse grain size is between 4 μm-5 μm, forming a unique microstructure where coarse grains were fully encapsulated by fine-grained regions. During plastic deformation, strain partitioning between coarse and fine grains facilitated synergistic strengthening mechanisms. This strain accommodation behavior effectively delayed crack initiation at grain boundaries while maintaining high work hardening capacity, thereby improving the overall mechanical performance.
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