MS-G技术调控Nd-Fe-B铸态组织研究  

Microstructure Regulation of As-cast Nd-Fe-B Alloy by MS-G Technology

作　　者：马斌 张鹏杰 王继全 李青华 李炳山 孙威 Ma Bin;Zhang Pengjie;Wang Jiquan;Li Qinghua;Li Bingshan;Sun Wei(BGRIMM Technology Group Co.Ltd,Beijing 102600,China;BGRIMM Magnetic Materials and Technology(Fuyang)Co.Ltd,Fuyang 236000,China)

机构地区：[1]矿冶科技集团有限公司,北京102600 [2]北矿磁材(阜阳)有限公司,安徽阜阳236000

出　　处：《中国稀土学报》2024年第1期47-52,I0002,共7页Journal of the Chinese Society of Rare Earths

基　　金：国家重点研发计划“稀土新材料”重点专项2021年度青年科学家项目(YFB3502400)资助。

摘　　要：采用熔体快淬+晶体生长(MS-G)技术调控Nd-Fe-B铸态组织,研究了铜辊转速及高温热处理对Nd-Fe-B快淬条带组织结构的影响。铜辊转速25 m·s^(-1)时快淬条带微观晶粒组织均匀,平均晶粒尺寸0.1μm,XRD图谱显示其为Nd_(2)Fe_(14)B相。Nd-Fe-B快淬条带经880℃热处理2.0 h晶粒均匀长大,平均尺寸0.86μm;冷却到750℃继续热处理2.0 h晶粒进一步均匀长大,平均尺寸达到1.04μm。温度升高会降低Nd_(2)Fe_(14)B晶粒异常长大临界驱动力Δg_(c),缩短异常长大的孕育期,使异常晶粒提早出现,高温+低温两步热处理通过降温处理来延长晶粒异常长大孕育期,从而促进Nd_(2)Fe_(14)B晶粒在较低温度下继续均匀长大。In this study,the as-cast Nd-Fe-B alloy was treated by the melt-spun and grain growth(MS-G) technology,and the effects of copper roll speed and high temperature treatment on the microstructure of Nd-Fe-B melt-spun strip were investigated.The melt-spun strip shows uniform grain structure with grain size of 0.1 μm at roll speed of 25 m·s^(-1) and the XRD pattern shows diffraction peaks of Nd_(2)Fe_(14)B phase.The Nd_(2)Fe_(14)B grains in 25 m·s^(-1) melt-spun strip grow uniformly to 0.6 μm when treated at 880 ℃ for 2.0 h,and then further grow to 1.04 μm after the second heat treatment at 750 ℃ for 2.0 h.The increase of temperature will reduce the critical driving force Δg_(c) for abnormal growth of Nd_(2)Fe_(14)B grains,as a result,shorten the incubation period and result in the earlier appearance of abnormal grains.The two-step heat treatment prolongs the incubation period of abnormal grain growth by cooling treatment,thereby,promoting the Nd_(2)Fe_(14)B grains to grow uniformly at a lower temperature.

关 键 词：钕铁硼 熔体快淬 晶体生长 两步热处理 铸态组织 

分 类 号：O482.54[一般工业技术—材料科学与工程]