过共晶Fe-Cr-B-C合金的快冷组织与性能  

Rapid Cooling Microstructure and Properties of Hypereutectic Fe-Cr-B-C Alloy

作　　者：牟楠[1] 卢静[1,2] 王冠 闵小兵 罗丰华 MU Nan;LU Jing;WANG Guan;MIN Xiaobing;LUO Fenghua(State Key Laboratory of Powder Metallurgy,Central South University,Changsha 410083,China;Hunan Metallurgy Material Institute,Changsha 410129,China)

机构地区：[1]中南大学粉末冶金国家重点实验室,湖南长沙410083 [2]湖南省冶金材料研究院,湖南长沙410129

出　　处：《热加工工艺》2018年第18期63-66,共4页Hot Working Technology

摘　　要：采用光学显微镜（OM）、附带能谱仪（EDS）的扫描电镜（SEM）、X射线衍射仪（XRD）及显微硬度计等方法,研究过共晶Fe-Cr-B-C合金的组织和性能。结果表明：铸态Fe-Cr-B-C合金的宏观硬度为66 HRC,冲击韧性达到6.4J/cm^2;该合金组织由板条马氏体基体和（Fe,Cr）2（B,C）、（Fe,Cr）3（B,C）、（Fe,Cr）23（B,C）6硬质相组成,硼碳化物主要呈长条状、块状、鱼骨状、蜂窝状及菊花状分布。经960℃退火2h后,合金的宏观硬度降低为52 HRC,冲击韧性减少到2.6 J/cm^2;基体转变为铁素体,且固溶的Cr、B含量减少;长条状和块状的初生（Fe,Cr）2（B,C）大量溶解,生成连续网状分布的共晶组织和二次硼碳化物。The microstructure and properties of hypereutectic Fe-Cr-B-C alloy were studied by optical microscope（OM）,scanning electron microscope（SEM）with energy dispersive spectrometer（EDS）,X-ray diffraction（XRD）and microhardness tester.The results show that the macrohardness of as-cast Fe-Cr-B-C alloy is 66 HRC and the impact toughness is 6.4 J/cm^2.The microstructure of the alloy consists of lath martensite matrix and（Fe,Cr）2（B,C）,（Fe,Cr）3（B,C）and（Fe,Cr）23（B,C）6hard phase.The distribution of boron carbide is mainly long strip,massive,fishbone,honeycomb and chrysanthemum shapes.After annealing at 960℃for 2 h,the macrohardness of the alloy reduces to 52 HRC,and the impact toughness reduces to 2.6 J/cm^2.The matrix transforms into ferrite,and the solid solution content of Cr and B reduces.The primary（Fe,Cr）2（B,C）with long strip and massive shapes dissolves in a large amount,and the eutectic structures and secondary carbon-boride in the distribution of continuous network form.

关 键 词：Fe-Cr-B-C合金 快冷 过共晶 退火 

分 类 号：TG142.7[一般工业技术—材料科学与工程]