CAJ | 학술논문

采用喷射成形工艺制备了含铌和不含铌M3：2型高速钢，然后进行锻造加工.利用扫描电子显微镜、X射线能谱仪、X射线衍射仪等研究了铌对喷射成形M3：2型高速钢组织和性能的影响.铌的加入细化了沉积态的组织，减小了M2 C共晶碳化物尺寸，而对M2 C的成分影响不明显.沉积态中MC碳化物的数量随铌含量提高而增多，且其成分变化显著.铌的加入可以提高喷射成形M3：2型高速钢的抗回火软化性和二次硬化能力.但是，当铌质量分数为1%时，组织中形成数量较多且难以破碎的以铌为主的块状MC碳化物，导致钢的弯曲强度和冲击韧性下降.铌质量分数为0.5%的喷射成形M3：2型高速钢可以获得最佳的硬度、弯曲强度和冲击韧性.
채용분사성형공예제비료함니화불함니M3：2형고속강，연후진행단조가공.이용소묘전자현미경、X사선능보의、X사선연사의등연구료니대분사성형M3：2형고속강조직화성능적영향.니적가입세화료침적태적조직，감소료M2 C공정탄화물척촌，이대M2 C적성분영향불명현.침적태중MC탄화물적수량수니함량제고이증다，차기성분변화현저.니적가입가이제고분사성형M3：2형고속강적항회화연화성화이차경화능력.단시，당니질량분수위1%시，조직중형성수량교다차난이파쇄적이니위주적괴상MC탄화물，도치강적만곡강도화충격인성하강.니질량분수위0.5%적분사성형M3：2형고속강가이획득최가적경도、만곡강도화충격인성.
AISI M3:2 high speed steels with or without niobium addition were prepared via spray forming, then subjected to forging processes. The effects of Nb on the microstructure and properties of the high speed steels were investigated by scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction. It is found that Nb addition can refine the microstructure of the as-deposited steels and decrease the size of M2 C eutectic carbides. The amount of MC carbides in the as-deposited steels increases with increasing Nb content. The tempering resistance and second hardening ability of the high speed steel are improved by Nb addition. With a 1% Nb addition, lots of bulk Nb-rich primary MC carbides can form, which becomes the main cause of the reduction in bending strength and impact toughness of the high speed steel. However, the best mechanical properties can be achieved in the presence of 0. 5% Nb.