CAJ | 학술논문

采用OM，SEM，EDS，TEM，EBSD，XRD等分析手段，研究了稀土和热处理对M42高速钢组织和性能的影响规律．结果表明，M2 C是M42高速钢主要的共晶碳化物类型．稀土处理后，M2 C共晶碳化物形貌由规则层片状变为不规则环状．尽管二者形貌差异明显，但具有相同的微观结构和晶体取向特征．与层片状碳化物相比，环状M2 C共晶碳化物热稳定性较差，高温加热时更易发生分解和球化，使碳化物尺寸明显细化．小尺寸碳化物在淬火加热时易于溶解，提高了淬火后基体中合金元素的固溶度，使M42高速钢硬度增加了1．5 HRC．
채용OM，SEM，EDS，TEM，EBSD，XRD등분석수단，연구료희토화열처리대M42고속강조직화성능적영향규률．결과표명，M2 C시M42고속강주요적공정탄화물류형．희토처리후，M2 C공정탄화물형모유규칙층편상변위불규칙배상．진관이자형모차이명현，단구유상동적미관결구화정체취향특정．여층편상탄화물상비，배상M2 C공정탄화물열은정성교차，고온가열시경역발생분해화구화，사탄화물척촌명현세화．소척촌탄화물재쉬화가열시역우용해，제고료쉬화후기체중합금원소적고용도，사M42고속강경도증가료1．5 HRC．
The influence of rare earth metals and heat treatment on the microstructure and performance of M42 steel has been investigated by means of an optical microscope OM scanning electron microscope SEM energy dispersive spectroscopy EDS transmission electron microscope TEM electron back-scatter diffraction EBSD and X-ray diffraction XRD . The results show that M2 C is the prevailing type of eutectic carbides in M42 steel. After modification with rare earth metals M2 C eutectic carbides change from the ordered lamellar structure into a circular structure.Despite different morphologies the two carbides present the same characteristics of microstructure and growth orientation.Compared with lamellar carbides M2 C carbides with the circular structure are much easier to decompose and spheroidize after heating which remarkably refines the carbide dimensions.The refined carbides improve the supersaturation of alloying elements in martensite and increase the hardness of M42 steel by 1.5 HRC.