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渗碳工艺是当前机械制造工业中应用最为广泛的一种化学热处理方法,它使被渗工件获得一定的强度、较高的耐磨性和疲劳抗力。被渗工件的机械性能主要决定于渗碳层中的碳浓度及淬火回火后的金相显微组织。当渗碳层中碳浓度较高时,淬火后具有针状马氏体和大块或网状碳化物以及数量较多的残留奥氏体。近年来又观察到当渗碳层的碳含量较高时会伴随针状马氏体出现一定数量的显微裂纹。若从疲劳强度考虑上面这些组织
Carburizing process is currently the most widely used in the machinery manufacturing industry, a chemical heat treatment method, which allows infiltration of work pieces to obtain a certain strength, high wear resistance and fatigue resistance. The mechanical properties of infiltrated workpieces are mainly determined by the carbon concentration in the carburized layer and the metallographic microstructure after quenching and tempering. When the carbon concentration in the carburized layer is high, there are acicular martensite and massive or reticular carbides after quenching, and a large amount of retained austenite. In recent years, it has also been observed that when the carbon content of the carburized layer is high, a certain amount of micro-cracks occur along with the acicular martensite. Consider these organizations from fatigue strength