Re对单晶镍基合金蠕变行为的影响  

Effects of Element Re on Creep Behavior of Single Crystal Nickel-base Superalloy

作　　者：王明罡[1,2] 田素贵[1] 夏丹[1] 于兴福[1] 钱本江[1] 

机构地区：[1]沈阳工业大学材料科学与工程学院,沈阳110078 [2]长春工业大学先进结构材料省部共建教育部重点实验室

出　　处：《特种铸造及有色合金》2009年第5期396-398,共3页Special Casting & Nonferrous Alloys

基　　金：国家自然科学基金资助项目(50571070);辽宁省教育厅基金资助项目(2004C004)

摘　　要：通过对有Re和无Re单晶镍基合金进行蠕变性能测定,结合组织形貌观察,研究了Re对单晶镍基合金蠕变行为的影响。结果表明,Re可有效提高合金的高温蠕变抗力,与无Re单晶合金相比较,加入2%的Re后,可使合金在高温低应力条件下的蠕变寿命有较大幅度的提高,计算出2%的Re合金在稳态蠕变期间的蠕变激活能Q=478.6kJ/mol,应力指数n=5.1。合金在蠕变初期的变形特征是(1/2)<110>位错在基体通道中滑移,运动位错相遇发生位错反应,在γ、γ′两相界面处形成位错网,可提高合金的蠕变抗力。蠕变后期,合金的变形机制是<110>超位错切入筏状γ′相内。Effects of element Re on creep behavior were examined by means of measuring creep curves and microstructural observation of the single crystal superalloy containing Re or Re-free.The results indicate that high temperature creep resistance of the single crystal alloy can be greatly improved with Re addition.Compared with those of the alloy containing Re-free,the creep activation energy and stress exponent of the alloy containing 2% Re element during steady creep process can reach up to 478.6kJ/mol and 5.1,respectively,showing a distinct increase in creep lifetimes at high temperature under the condition of low stress.<110>dislocation slipping during initial creep was activated in the matrix channel to form dislocation net-like structure on γ/γ' phase interface by dislocation reaction among moved dislocations,which is responsible for the improvement of creep resistance of the single crystal alloy,while <110> super-dislocation during completed creep is sheared into the rafted γ' phase.

关 键 词：单晶镍基合金 RE 组织结构 蠕变特征 

分 类 号：TG146.15[一般工业技术—材料科学与工程]