单晶镍基合金的蠕变特性及影响因素
来源期刊:中国有色金属学报2000年第1期
论文作者:田素贵 张禄廷 张静华 杨洪才 徐永波 胡壮麒
文章页码:43 - 46
关键词:单晶镍基合金;合金元素;蠕变抗力;位错攀移
Key words:single crystal nickel-base superalloys; alloying elements; creep resistance; dislocation climb
摘 要:通过对[001]取向单晶镍基合金蠕变曲线和位错运动内摩擦力的测定及能谱微区成分分析,研究了两种合金的蠕变特性。结果表明:在1000 ℃和120MPa条件下,两合金位错运动的内摩擦力值相近,随温度的升高,两合金的内摩擦力差值增大;随着温度的提高,不含Ta的合金中γ' 相尺寸和体积分数明显减少,而Al和Ta元素含量较高的合金中,γ' 相保持较高的体积分数是合金蠕变抗力明显提高的主要原因。
Abstract: The affection factors of the creep behaviour for two single crystal nickel-base superalloys with [001] orientation were studied by measuring the creep curves and internal stress of dislocation motion, and by EDAX composition analysis as well. It is shown that the size and volume fraction of the γ' phase in alloy containing no element Ta are obviously decreased with the increasing of temperature. The main reason for the better creep resistance of the alloy, containing more elements Ta and Al, during steady creep is that it keeps a high volume fraction of γ' phase.