相场法研究含第二相颗粒多晶体系的晶粒粗化标度律  

A PHASE FIELD STUDY FOR SCALING RULES OF GRAIN COARSENING IN POLYCRYSTALLINE SYSTEM CONTAINING SECOND-PHASE PARTICLES

作　　者：赵彦[1] 张洪宇[1] 韦华[1] 郑启[1] 金涛[1] 孙晓峰[1] 

机构地区：[1]中国科学院金属研究所,沈阳110016

出　　处：《金属学报》2013年第8期981-988,共8页Acta Metallurgica Sinica

基　　金：国家重点基础研究发展计划项目201B631206;国家自然科学基金项目50931004;51071164和50671102资助~~

摘　　要：利用相场法研究了第二相颗粒体积分数对多晶体系晶粒粗化标度律的影响.结果表明:随着第二相颗粒体积分数增加,晶粒生长阻力增大,晶粒平均半径R_a随时间t的演化关系偏离t=AR_a^m+B非线性关系,且动力学指数m随第二相颗粒体积分数增加而增大.在晶粒粗化阶段,无论第二相颗粒是否存在,及第二相颗粒体积分数的大小,系统均满足标度律.随着第二相颗粒体积分数增加,系统结构因子曲线的峰值逐渐降低,且当波矢k值增大到某一值后,系统结构因子曲线基本重合;随着第二相颗粒体积分数增加,系统标度函数峰值降低,峰宽变宽.在较大的k值情况下,同一k值对应的标度函数值随第二相颗粒体积分数的增加而增大.由结构因子和标度函数可知,第二相颗粒体积分数增加,晶粒间的相互作用减弱,晶粒粗化过程中的尺寸均匀性将更好.The kinetic scaling of the grain coarsening in the polycrystalline system containing the dispersive second-phase particles was studied by phase field method. The obtained results showed that the increase in the volume fraction of second-phase particles enhanced the growth resistance of grain, resulting in the remarkable deviation of the relationship between the average grain radius Ra and the time t from the non-linear relationship t=ARma＋B. The kinetic exponent rn also increased with the increasing volume fraction of second-phase particles. No matter whether the second-phase particles existed or not in the system studied, the scaling rule had been satisfied at the late stage of grain coarsening. The increase in the volume fraction of the second-phase particles would cause the decrease in the peak value of structure factor profile. When the value of the wave vector k increased to a certain value, the structure factor curve of the studied system was essentially coincident. With the increase in the volume fraction of second phase particles, The peak values of scaling function decreased and the peak width became wider. According to structure factor and scaling function, it was known that with the increase in the volume fraction of second-phase particles, the interaction among grains weakens and the grain size would become more uniform during the grain coarsening.

关 键 词：相场方法 粗化动力学 结构函数 标度律 

分 类 号：TG111[金属学及工艺—物理冶金]