Finite element analysis of thermal residual stresses at cemented carbide rock drill buttons with cobalt-gradient structure  

作　　者：黄自谦 贺跃辉 蔡海涛 肖逸锋 黄伯云 

机构地区：[1]State Key Laboratory of Powder Metallurgy,Central South University [2]School of Mathematical Sciences and Computing Technology,Central South University

出　　处：《中国有色金属学会会刊：英文版》2008年第3期660-664,共5页Transactions of Nonferrous Metals Society of China

基　　金：Project(50323008) supported by the National Natural Science Foundation of China

摘　　要：The aim of this study is to apply the concept of functionally graded materials(FGMs) to cemented carbides and to develop high-performance rock drill buttons. Cobalt-gradient structure was introduced to the surface zone of the buttons by carburizing process. Finite element method and XRD measurement were used to decide the distribution of thermal residual stress. Constitutive parameters were determined by constraint factor. Numerical results show that residual stresses of gradient buttons mainly concentrate in cobalt-gradient zone. There is compressive stress in the surface zone and tensile stress in the cobalt-rich zone. The maximum value of surface compressive stress is 180 MPa for WC-6Co cemented carbides. And the numerical results agree with the results of XRD measurement.The aim of this study is to apply the concept of functionally graded materials（FGMs） to cemented carbides and to develop high-performance rock drill buttons. Cobalt-gradient structure was introduced to the surface zone of the buttons by carburizing process. Finite element method and XRD measurement were used to decide the distribution of thermal residual stress. Constitutive parameters were determined by constraint factor. Numerical results show that residual stresses of gradient buttons mainly concentrate in cobalt-gradient zone. There is compressive stress in the surface zone and tensile stress in the cobalt-rich zone. The maximum value of surface compressive stress is 180 MPa for WC-6Co cemented carbides. And the numerical results agree with the results of XRD measurement.

关 键 词：超硬合金 钴梯度结构 有限元方法 约束因素 

分 类 号：TB302[一般工业技术—材料科学与工程]