细晶Cr-NbCr_2合金的热稳定性（英文）  

Thermal Stability of Fine-Crystal Cr-NbCr_2 Alloy

作　　者：邓莉萍[1,2] 鲁世强 汤斌兵[3] 

机构地区：[1]南京航空航天大学,江苏南京210016 [2]南昌航空大学,江西南昌330063 [3]南昌大学,江西南昌330063

出　　处：《稀有金属材料与工程》2018年第1期7-12,共6页Rare Metal Materials and Engineering

基　　金：National Natural Science Foundation of China(51074092);Natural Science Foundation of Jiangxi Province(20161BAB206113);KJLD Plan Projects of Jiangxi Provincial Education Department(KJLD14056)

摘　　要：研究了通过机械合金化+热压工艺制备的细晶Cr-NbCr_2合金的热稳定性。结果表明:热暴露过程中,Cr基体的颗粒尺寸有一定程度的长大,而Laves相NbCr_2颗粒由于其高热稳定性无明显变化。随着热暴露的进行,Cr基体颗粒与Laves相NbCr_2颗粒间压应力增加,使得基体和Laves相中分别出现了位错和层错/孪晶结构。颗粒尺寸的变化和晶体缺陷的出现,使得Cr-NbCr_2合金在800~1200℃热暴露50 h后仍具有较高的抗压强度,屈服强度和良好的塑性。但随着热暴露的继续延长,此时颗粒的长大成为主导因素,Cr-NbCr_2合金的屈服强度和塑性明显下降。Thermal stability of the fine-crystal Cr-NbCr2 alloy prepared by mechanical alloying and hot pressing was researched. The results show that the grain size of Cr matrix has a certain degree of growing up after the thermal exposure, while the particle size of Laves phase NbCr2 has no obvious change due to its high thermal stability. At the same time, the dislocation in the Cr matrix and the stacking faults/twins in the Laves phase NbCr2 particles appear in the as-thermaUy exposed microstructure because of the increase of the compressive stress between Cr matrix and NbCr2 particles. Due to the variation in particle size and the occurrence of crystal defects, the Cr-NbCr2 alloy can keep higher compressive strength, yield strength and plastic strain after thermal exposure from 800 ℃ to 1200 ℃ for 50 h. However, the yield strength and plastic strain of the Cr-NbCr2 alloy decline obviously by prolonging the thermal exposure because the growth of grains becomes the determining factor of properties.

关 键 词：Cr-NbCr2合金 细晶 热稳定性 晶体缺陷 

分 类 号：TG144[一般工业技术—材料科学与工程]