Ni_(75)Al_xCr_(25-x)合金时效组织演变行为微观相场模拟  

Microscopic Phase-field Simulation for Microstructure Evolution of Ni_(75)Al_xCr_(25-x) Alloy

作　　者：张济祥[1] 陈铮[1] 来庆波[1] 赵彦[1] 

机构地区：[1]西北工业大学材料科学与工程学院

出　　处：《有色金属》2011年第1期38-42,共5页Nonferrous Metals

基　　金：国家自然科学基金资助项目(50671084;50875217);中国博士后科学基金项目(20070420218)

摘　　要：利用三元微观相场动力学模型,结合原子图像、有序相颗粒半径和和体积分数等手段模拟研究不同浓度的Ni75AlxCr25-x合金973K下的时效组织演变行为。结果表明,x=6,8,10三种Ni75AlxCr25-x合金时效过程中均析出DO22和L12两种有序相。随着Al含量的增加,L12相颗粒的尺寸增大,体积分数增加,相应的DO22相颗粒的尺寸减小,体积分数减少。无论DO22相还是L12相,在考虑弹性畸变能的影响后,有序相颗粒平均半径的立方与时间之间仅仅在粗化初期的某一阶段,近似的呈线性关系。整体上来看,不满足LSW粗化理论。The microstructure evolution of Ni75AlxCr25-x alloy aging at 973K is simulated with ternary microscopic phase-field and investigated by means of atomic pictures,particle radius and volume fraction.The results show that DO22 and L12 ordered phases are formed during the aging of Ni75AlxCr25-x alloy for x=6,8 and 10,respectively.The particle size and volume fraction of L12 phase are increased,correspondingly,the particle size and volume fraction of DO22 phase are decreased with the increase of Al content.Considering the effects of elastic strain energy,on the whole,the coarsening behavior of both DO22 phase and L12 phase do not follow the time-law predictions of LSW theory of diffusion controlled growth,and there exists linear relation between the particle radius and time only at the early stage of precipitation.

关 键 词：金属材料 Ni75AlxCr25-x合金 微观相场法 体积分数 原子图像 

分 类 号：TG113.12[金属学及工艺—物理冶金] TG146.4[金属学及工艺—金属学]