【摘要】 采用X—射线衍射分析、TEM组织观察和电子衍射分析,对新型半高速钢在加热和冷却及回火过程中碳化物的溶解和析出行为进行了研究。结果表明,退火状态下钢中含有MC、M6C和M7C3 型碳化物;淬火加热时M6C和M7C3 型碳化物全部溶解,回火过程中析出MC、M2C、M6C和M7C3 型碳化物,当回火温度为520 ℃时出现硬度峰值,此时Mo2C的弥散强化起主要作用。更多还原

【Abstract】 The dissolution and precipitation during heating, cooling and tempering of a new kind of semi high speed steel were studied by means of X-ray diffraction analysis, TEM microstructure examination and electron diffraction. The results showed that in the annealed state there are MC,M₆C and M₇C₃ in the steel; M₆C and M₇C₃ are dissolved totally during heating for quenching, MC,M₂C, M₆C and M₇C₃ are precipitated during tempering. The peak hardness of the steel is reached after tempering at 520 ℃. The precipitation strengthening of the Mo₂C is the main factor of strengthening in this case.更多还原