【摘要】 利用光学显微镜(OM)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和电子背散射衍射仪(EBSD)等研究了不同调质工艺对C95级石油套管用钢组织的影响。结果表明:直接淬火后试验钢的奥氏体沿着轧制方向拉长,呈扁平状,再加热淬火后试验钢组织则为等轴状;随着调质回火温度的升高,马氏体板条合并,尺寸变宽,板条边界模糊,同时析出的碳化物也明显粗化,相邻晶粒小角度晶界比例降低;直接淬火试验钢与再加热淬火试验钢相比,其板条更细小、位错密度更高、相邻晶粒小角度晶界比例更高。更多还原

【Abstract】 Effects of qucenching and tempering on microstructure of C95oil casing steel were investigated by optical microscopy(OM),scanning electron microscopy(SEM),transmission electron microscopy(TEM)and electron backscatter diffraction(EBSD).The results show that the austenite in test steel after direct quenching was elongated as flat shape along the rolling direction,while it was equiaxial after reheating quenching.As the tempering temperature increasing,martensite laths merged,the size of martensite laths became wider,the boundaries of laths were blured,the precipitated carbides were coarsened,and the proportion of low-angle grain boundary between neighboring crystallographic grains decreased in the test steel.The test steel after direct quenching had smaller martensite laths,higher dislocation density and higher ratio of low-angle grain boundary between neighboring crystallographic grains compared to the reheat quenched test steel.更多还原