GH4169合金晶界δ相析出的动力学分析  

Precipitation Kinetic Analysis for δ Phases at Grain Boundary of GH4169 Alloy

作　　者：王建国[1] 刘东[1] 王海平 杨艳慧[1] 付保全 杜刚[2] 王新[3] Wang Jianguo;Liu Dong;Wang Haiping;Yang Yanhui;Fu Baoquan;Du Gang;Wang Xin(Northwestern Polytechnical University,Xi'an 710072,China;Western Superconducting Technologies Co.Ltd,Xi'an 710018,China;Shandong Taishan Iron & Steel Group Co.Ltd,Laiwu 271100,China)

机构地区：[1]西北工业大学,陕西西安710072 [2]西部超导材料科技股份有限公司,陕西西安710018 [3]山东泰山钢铁集团有限公司,山东莱芜271100

出　　处：《稀有金属材料与工程》2019年第4期1148-1154,共7页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51504195)

摘　　要：通过对固溶态及变形态GH4169合金进行时效处理,采用SEM技术研究Nb元素含量、晶界曲率对合金中δ相体积分数及尺寸的影响,讨论了δ相在弯曲界面析出的动力学规律。结果表明:GH4169合金中δ相析出的体积分数随Nb元素含量的增加而增加,δ相析出的峰值温度为920℃且受Nb元素含量的影响较小。随试样平均晶粒尺寸的减小,δ相的形核率和体积分数增加,δ相尺寸减小。小角度晶界可有效促进δ相在晶粒内部析出。随晶界曲率半径的减小,δ相形核的临界势垒和临界半径减小,晶界δ相的形核率增加。在晶界析出δ相分别呈长针状、锯齿状及鱼尾状分布。GH4169 alloys which were solution treated and deformed at high temperature were conducted on aging treatment to investigate the morphology and precipitation mechanisms of δ phases. The results show that the volume fraction of δ phases increases with the increase of Nb element content. The peak temperature for δ phases precipitation is 920 ℃ which is slightly influenced by the content of Nb element. The nucleation rate and volume fraction of δ phases increase with the decreasing of average grain size. Otherwise, the size of δphases decreases with the decrease of average grain size. Low angle grain boundaries within grains promote the precipitation of δ phases intergranular. The critical barrier and critical radius decreases with the decrease of the radius of curvature. Otherwise, the nucleation rate ofδ phases increases with the decreasing of curvature. The distribution morphologies of δ phases precipitated at grain boundary are similar to needles, sawteeth and fish tails.

关 键 词：GH4169合金 δ相形貌 晶界曲率 

分 类 号：TG146.15[一般工业技术—材料科学与工程]