Cr-N化合物析出相形成能的第一性原理计算  

First-principles Calculation of Formation Energy of Cr-N Compound Precipitations

作　　者：杜畅[1] 曹凤婷 李旭[1] DU Chang;CAO Fengting;LI Xu(Hebei Key Laboratory for Mining Equipment Safety Monitoring, North China Institute of Science and Technology, Langfang Hebei 065201, China;Tianjin University of Technology and Education, Tianjin 300222, China)

机构地区：[1]华北科技学院河北省矿山设备安全监测重点实验室,河北廊坊065201 [2]天津职业技术师范大学,天津300222

出　　处：《上海金属》2021年第2期114-118,共5页Shanghai Metals

基　　金：廊坊市科学技术研究与发展计划(2020011014);中央高校基本科研业务费专项资金(3142019055);“河北省矿山设备安全监测重点实验室”资助。

摘　　要：CrN和Cr_(2)N是不锈钢氮化层中典型析出相,其析出倾向和长大方式决定了两者的数量、形态和分布,进而影响氮化层的性能。采用第一性原理计算了不锈钢氮化层中CrN和Cr_(2)N析出相的形成能,建立了CrN/α-Fe和Cr_(2)N/α-Fe两种界面模型并计算了界面形成能。结果表明:CrN相形成能和CrN/α-Fe界面形成能均低于Cr_(2)N的相关形成能,从能量角度看,CrN的析出更具优势,从而解释了不锈钢表面氮化层中CrN较Cr_(2)N优先析出的原因。CrN and Cr_(2)N are typical precipitates in the nitrided stainless steels,their precipitation tendency and growth mode determine the amount,morphology and distribution of the two,and thus effecting the properties of nitriding layer.The first-principles calculation was employed to calculate the formation energy of CrN and Cr_(2)N in the nitriding layer of stainless steels,and to establish the interface models of CrN/α-Fe and Cr_(2)N/α-Fe as well as calculate their interface formation energy.The results showed that the formation energy of CrN phase and CrN/α-Fe interface was lower than that of Cr_(2)N,and CrN was more prone to precipitate from the angle of energy,which explained why CrN precipitate occurred preferentially than Cr_(2)N in the nitriding layer of stainless steel surface.

关 键 词：CRN Cr_(2)N 形成能 界面 第一性原理 

分 类 号：TG1[金属学及工艺—金属学]