析出相对GH141宏观残余应力的影响  

Effect of Precipitates on Macroscopic Residual Stress of GH141

作　　者：刘谨[1] 赵志毅[1] 薛润东[1] 

机构地区：[1]北京科技大学材料科学与工程学院,北京100083

出　　处：《稀有金属》2017年第11期1258-1264,共7页Chinese Journal of Rare Metals

基　　金："十三五"国家重点研发计划项目(2016YFB0300200)资助

摘　　要：通过小孔法和场发射扫描电镜(FE-SEM)分别测试观察了GH141高温合金在不同过时效温度下残余应力的变化和γ'析出相形态的演变,研究了微观析出相的改变对宏观残余应力的影响。结果表明,只有一次过时效处理时,选择10个温度实验点,随着温度从1000℃降低到810℃,残余应力数值从54 MPa逐渐增大到98 MPa,增加了81%,且增长速度总体呈现先快后慢的趋势。微观统计分析表明,γ'析出相数量及体积分数这两者变化趋势与残余应力变化趋势相一致;在有多次时效工艺处理时,第一次时效温度越低,γ'相体积变小且数量增多,第二次时效温度越低,γ'相体积不变而数量增多。残余应力的测试结果表明,只有γ'相体积分数与残余应力变化趋势一致。经对比分析得出结论,在析出应力占主导的情况下,γ'析出相体积分数是影响GH141宏观残余应力变化的唯一微观因素。Evolution of residual stress and precipitate pattern of GH141 superalloy under overaging treatments at different tempera tures were tested by hole drilling method and field emission scanning electron microscopy （FE-SEM）. Effect of microscopic precipitates on macroscopic residual stress of GH141 was studied. The results indicated that under once overaging treatments, as the ten temperature points reduced from 1000 to 810 ℃ , residual stress value increased gradually from 54 to 98 MPa, increased by 81% and the tendency of increase hurry first then slow. Microscopic statistical analysis showed that the variation of the particle number and volume fraction of γ＇ precipitates was consistent with residual stress. Under multiple overaging treatments, the low first aging temperature made the γ＇ grain minify and quantity increased, whereas the low second aging temperature raised the particle number but volume invariant. The variation of the volume fraction of γ＇ precipitates was the only one consistent with residual stress. Come to the conclusion by contrast a- nalysis, in the case of precipitation stress hold a dominant position, the variation of the volume fraction of γ＇ precipitates was the one and the only one microscopic factor consistent with residual stress.

关 键 词：GH141 时效 应力 析出相 

分 类 号：TG132.3[一般工业技术—材料科学与工程]