Growth kinetics of cubic carbide free layers in graded cemented carbides

作     者：Liu-yong Shi Yi-min Liu Ji-hua Huang Shou-quan Zhang Xing-ke Zhao 

作者机构：School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China College of Mechanical and Electrical engineering Hainen University Danzhou 571737 China Xiarnen Golden Egret Special Alloy Co. Ltd. Xiamen 361006 China 

出 版 物：《International Journal of Minerals,Metallurgy and Materials》 (矿物冶金与材料学报（英文版）)

年 卷 期：2012年第19卷第1期

页      面：64-71页

核心收录：

学科分类：0709[理学-地质学] 0819[工学-矿业工程] 07[理学] 070205[理学-凝聚态物理] 08[工学] 0806[工学-冶金工程] 0708[理学-地球物理学] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0703[理学-化学] 0802[工学-机械工程] 0702[理学-物理学] 0801[工学-力学（可授工学、理学学位）] 

基　　金：financially supported by the National Key Technology Support Program (No.2007BAE05B02) 

主　　题：graded materials cemented carbides diffusion kinetics 

摘      要：In order to reveal the formation mechanism of cubic carbide free layers （CCFL）, graded cemented carbides with CCFL in the surface zone were fabricated by a one-step sintering procedure in vacuum, and the analysis on microstructure and element distribution were performed by scanning electron microscopy （SEM） and electron probe micro-analyzer （EPMA）, respectively. A new physical model and ki- netic equation were established based on experimental results. Being different f^om previous models, this model suggests that nitrogen diffu- sion outward is only considered as an induction factor, and the diffusion of titanium through liquid phase plays a dominative role. The driving force of diffusion is expressed as the differential value between nitrogen partial pressure and nitrogen equilibrium pressure essentially. Simulation results by the kinetic equation are in good agreement with experimental values, and the effect of process parameters on the growth kinetics of CCFL can also be explained reasonably by the current model.