球磨时间对M2粉末冶金高速钢组织与力学性能的影响  

Effect of milling time on the microstructure and mechanical properties of M2 powder metallurgy high speed steel

作　　者：杨军浩 刘如铁[1] 熊翔[1] 栾怀壮 郝彦荣 杨宝震 陈洁[1] YANG Junhao;LIU Rutie;XIONG Xiang;LUAN Huaizhuang;HAO Yanrong;YANG Baozhen;CHEN Jie(State Key Laboratory of Powder Metallurgy,Central South University,Changsha 410083,China)

机构地区：[1]中南大学粉末冶金国家重点实验室,长沙410083

出　　处：《粉末冶金材料科学与工程》2020年第4期296-303,共8页Materials Science and Engineering of Powder Metallurgy

基　　金：国家重点研发计划资助项目(2016YFB0700302)。

摘　　要：以羰基铁粉与碳化物粉末为原料,经过0~72 h高能球磨后双向压制成形,然后于1205℃烧结1 h,制得M2粉末冶金高速钢,研究球磨时间对M2钢的碳氧含量、显微组织与力学性能的影响。结果表明,随球磨时间延长和原料混合粉末粒径减小,M2钢的氧含量显著提高,由于碳热反应,碳含量显著降低。M2钢的物相主要为Fe,M6C,M2C与MC相,随球磨时间延长,亚稳态M2C型碳化物减少,M6C与MC型碳化物增多。随球磨时间延长,M2钢的晶粒与碳化物尺寸变得细小,碳化物分布更均匀,M2钢的相对密度、硬度以及抗弯强度均明显提高。在球磨72 h条件下制备的高速钢相对密度为99.3%,硬度(HRC)和抗弯强度分别为50.6和2852 MPa。The M2 powder metallurgy high speed steel(PM HSS)was prepared with the carbonyl iron powders and carbide powders as raw materials.The powders were mixed via ball milling for 0−72 h,and then compacted by double-action pressing before sintered at 1205℃for 1h.The effect of the milling time on the carbon content,oxygen content,microstructure and mechanical properties of the M2 PM HSS were studied.The results show that with the increase of milling time,the particle size of the mixed powders decreases,the oxygen content increases significantly,and the carbon content of the M2 PM HSS decreases due to the carbon-thermal reduction.The main phases of M2 PM HSS are Fe,M6C,M2C and MC.With increasing milling time,metastable M2C carbide decreases,while M6C and MC carbides increase.Besides,with the increasing of milling time,the grain size of M2 PM HSS and particle size of carbide become finer,the carbide distribution is more uniform,and the relative density,hardness and bending strength of M2 PM HSS increase significantly.After milling for 72 h,the relative density of M2 PM HSS is 99.3%,and the hardness(HRC)and the bending strength are 50.6 and 2852 MPa,respectively.

关 键 词：粉末冶金高速钢 碳氧含量 显微组织 力学性能 碳化物 

分 类 号：TG142.1[一般工业技术—材料科学与工程]