粉末冶金铍-铝合金高温蠕变行为试验研究  

Study on high-temperature creep behavior of beryllium-aluminum alloy in powder metallurgy

作　　者：吕一格 刘喜军 张健康 赵志灵 LV Yi-ge;LIU Xi-jun;ZHANG Jian-kang;ZHAO Zhi-ling(State Key Laboratory of Special Rare Material,Northwest Rare Metal Material Institute,Shiznishan 753000,China)

机构地区：[1]西北稀有金属材料研究院宁夏有限公司,稀有金属特种材料国家重点实验室,宁夏石嘴山753000

出　　处：《轻合金加工技术》2020年第6期47-52,共6页Light Alloy Fabrication Technology

基　　金：国家自然科学基金(51474177);宁夏自然科学基金(2018AAC03226)。

摘　　要：通过高温拉伸蠕变试验,研究温度和应力对粉末冶金铍-铝合金[w(Be)=62%、w(Al)=38%]的短时蠕变行为的影响。研究结果表明:随着温度或应力的提高,合金的蠕变率先增大后基本保持不变,极限蠕变率为2.16%。铍-招合金的蠕变过程中,位错滑移和孪晶蠕变对低温低应力蠕变过程起着关键作用,而位错攀移对高温蠕变起着重要作用。温度为473.15 K,合金的应力指数为3.19;在应力150 MPa下,铍-铝合金的蠕变激活能为22.41 kJ/mol。在低应力蠕变状态下,铝相是蠕变中载荷的承载体;随着蠕变应力的增加,铍相逐渐成为蠕变过程中载荷的主要承载体。The effects of temperature and stress on beryllium-aluminum alloy[w(Be)=62%、w(Al)=38%]in powder metallurgy were researched by stretching creep experiment at high temperature.The result shows that the creep rate is increased and then basically remain unchanged with the increasing stress or temperature.The creep rate limit is 2.16%.The dislocation slip and crystal twin creep play a key role in the creep progress at low temperature and stress,while the dislocation climbing play a key role in creep progress at high temperature.The stress index of beryllium-aluminum alloy is 3.19 at 473.15 K.The creep activation of beryllium-aluminum alloy is 22.41 kj/mol under 150 MPa.At the same time,it is found that aluminum phase is the load-bearing body in creep under low stress creep and beryllium phase is the main load-bearing body in creep process with the increase of creep stress.

关 键 词：铍-铝合金 高温蠕变 蠕变率 蠕变机制 

分 类 号：TG146.24[一般工业技术—材料科学与工程]