温度对L1_0到L1_2有序转化中原子占位影响的相场模拟  

Phase-field Simulation for Influence of Temperature on Atomic Site Occupation of L1_0 to L1_2 Ordering Behavior

作　　者：郑晓娟[1] 赵宇宏[1] 侯华[1] 靳玉春[1] 马庆爽 田晋忠 

机构地区：[1]中北大学材料科学与工程学院

出　　处：《特种铸造及有色合金》2017年第1期26-29,共4页Special Casting & Nonferrous Alloys

基　　金：国家科技部国际科技合作项目(2014DFA50320);国家自然科学基金资助项目(51574207;51574206;51204147;51274175)

摘　　要：基于三元微观相场动力学模型模拟了在弹性畸变能常数B=800时,不同温度对Ni_(75)Al_(14)Mo_(11)合金沉淀过程的影响。结果表明,该合金首先析出L1_0相,其大部分为L1_0(II)型;随着时效的进行,基体中L1_0相全部转变为L1_2相;在弹性畸变能与温度的综合作用下,Ni_(75)Al_(14)Mo_(11)合金的有序化和簇聚变化量很小。Ni原子倾向于占据α位和β1位;Al、Mo原子倾向于占据β_2位,但Al原子占位几率远大于Mo原子;最终,在同一畸变能下,随着温度的升高,在各位置上Ni、Mo原子占位几率下降,Al原子占位几率增加。Based on the microscopic phase-field dynamic model,the precipitation process of Ni75Al14Mo11 alloy was simulated at elastic strain energy B=800 and different temperatures.The microscopic morphology evolution,average order parameters and atom occupation probabilities were analyzed.The results show that L10 phases is precipitated from the Ni75Al14Mo11 alloy firstly,and most of them are L10（II）phases,then all of the L10 phases are transformed into L12 phase in the following time.With the both influence of temperature and elastic strain energy,the Ni75Al14Mo11 alloy clustering and ordering exhibit slight change.Ni atom trends to occupy the α and β1 positions,while Al and Mo atoms trend to occupy the β2 position,however,the occupation probabilities of Al atoms are much higher than Mo atoms,and they commonly form Ni3（Al、Mo）phases.Eventually,with the increase of the temperature at B=800,the occupation probabilities of Ni and Mo atoms are reduced,while the occupation probabilities of Al atom are increased at every position.

关 键 词：Ni75Al14Mo11合金 L10结构 温度 有序化和簇聚 占位几率 

分 类 号：TG146.15[一般工业技术—材料科学与工程]