Experimental Study Of High Speed Steel Cryogenic Treatment Process Performance And Residual Stress Right

In the mechanical manufacturing industry, metal cutting tool has animportant position, and high speed steel as a common used tool material, it hasspecial characteristics of high hardness, wear resistance, enough strength andtoughness, high heat resistance, good thermal physical properties and thermalshock performance. However, those high qualities are obtained with heattreatment. Heat treatment can get the inner quality of expected (organization,structure and performance) via controlling the heating and cooling process ofmaterial or workpiece. Recent years, the heat treatment technology became thekey manufacturing technology in modern manufacturing with its rapiddevelopment. The heat treatment is inseparable in the field of industry,machinery, metallurgy, transportation, textile, aerospace and other industries.Heat treatment technology has made an important contribution for the upgrading,quality improving and life extension of mechanical and manufacturing product.This topic proposed cryogenic treatment technology can effectivelyenhance hardness, red hardness of the high-speed steel specimen because ofretained austenite transferring to martinets and precipitation of small carbidesand improve the residual stress on the surface of the specimen after heattreatment. The results were verified in the experiment, and showed thatcryogenic treatment can enhance its performance and surface residual stress inheat treatment. For further research on high speed steel specimen surface heattreatment after cryogenic treatment, the residual stress state, this topic byadopting the combination of experiment and simulation method were studied.The main research content includes the following several aspects:1) The paper proposed the process scheme for heat treatment, andconducted the vacuum quenching, tempering and cryogenic treatment.2) The paper studied the influence of the various cooling speed, cryogenictime, cryogenic temperature and tempering numbers on the specimen hardness,the microstructure, and red hardness, then analyzed the results.3) The paper described the heat residual stress in theory and its measuring methods. Finally, the experiment with the blind-hole method was conducted tomeasure the residual stresses under different processes, and to compare theinfluence of various factors on the residual stress in the specimens.Authors would like to thank the Natural Science Foundation of China(NSFC) for financial support (No.51275333)...