低Al含量Ni-Cr-Al合金有序化及相边界演化的数值模拟
褚 忠1, 赵国群1, 陈 铮2
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作者单位:1. 山东大学 材料学院, 山东 济南 250061; 2. 西北工业大学 材料学院, 陕西 西安 710072
中文关键字:微观相场模型; Ni-Cr-Al; 沉淀; 有序化参数; 模拟
英文关键字:microscope phase-field model; Ni-Cr-Al; precipitation; ordering parameters; simulation
中文摘要:基于三元微观相场模型,模拟研究了873 K时低Al含量三元合金Ni-Cr-Al有序化及相边界演化过程。研究发现,合金Ni-11Cr-7Al(原了百分数,下同)沉淀机制为非经典形核长大,沉淀过程中L12有序相伴随着DO22有序相的形核长大,同时,部分DO22有序相向L12有序相转化。由于Cr原子替代Al原子位置,在L12有序相内两种原子占位几率接近,形成Ni3(CrxAl1-x)结构的L12有序相,并且与DO22有序相共存。
英文摘要:The evolution of ordering and phase boundary of low- Al Ni-Cr-Al ternary alloy was studied at 873 K based on ternary microscope phase-field model. It is found that the precipitation mechanism of Ni-11Cr-7Al alloy is non-classical nucleation and growth, the nucleation and growth of L12 ordering phase are concomitant with DO22 ordering phase, and part of DO22 ordering phase transforms into L12 ordering phase. The occupation possibility of Al and Cr in L12 ordering phase is similar because of substitution behavior of Cr atom, Ni3(CrxAl1-x) structure forms and coexists with DO22 ordering phase.