【摘 要】
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This study aimed to explore the evolution of flow lines and microstructures of M50-steel bearing ring and the anisotropy of its tensile mechanical properties after Multi-Stage Hot Forging(MSHF) and subsequent spheroidizing annealing (MSHFA).To this end,th
【机 构】
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National Key Laboratory for Precision Hot Processing of Metals,Harbin Institute of Technology,Harbin
论文部分内容阅读
This study aimed to explore the evolution of flow lines and microstructures of M50-steel bearing ring and the anisotropy of its tensile mechanical properties after Multi-Stage Hot Forging(MSHF) and subsequent spheroidizing annealing (MSHFA).To this end,the present study mainly employed stereo microscopy,Optical Metallurgical Microscopy (OMM),Scanning Electron Micro-scopy (SEM),and Electron Backscatter Diffraction (EBSD) to characterize and analyze the work-piece at each processing stage of MSHF while performing microhardness measurement and uniaxial tensile experiment to test and analyze the mechanical properties of the workpiece.Macro-structure observation showed that the simulation results of flow lines at each stage were consistent with the experimental results.Microscopic observation showed that,after MSHF,deformation gradually became less significant along the outward radial direction of the bearing ring.After MSHFA,the microstructures of the bearing ring became uniform,whereas primary carbides did not dissolve.The mechanical properties were better in the axial direction (AD) than in the radial (RD) and cir-cumferential directions (CD) after MSHF due to the smaller grain width.After MSHFA,the mechanical properties in the ADs and CDs were better than those in the RDs,which was due to the large cross-sectional area of carbides along the flow-line direction.
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