单晶镍基高温合金在600～760℃下的低循环疲劳行为  

Low Cycle Fatigue Behaviors of Single Crystal Nickel-based Superalloy at Temperatures of 600～760 ℃

作　　者：张志华 于慧臣 李影 董成利 ZHANG Zhihua;YU Huichen;LI Ying;DONG Chengli(AECC Beijing Institute of Aeronautical Materials, Beijing 100095, China;Science and Technology on Advanced High Temperature Structural Materials Laboratory, Beijing 100095, China;Key Laboratory of Aeronautical Materials Testing and Evaluation, Aero Engine Corporation of China, Beijing 100095;Beijing Key Laboratory of Aeronautical Materials Testing and Evaluation, Beijing 100095, China)

机构地区：[1]中国航发北京航空材料研究院,北京100095 [2]先进高温结构材料科技重点实验室,北京100095 [3]中国航空发动机集团材料检测与评价重点实验室,北京100095 [4]航空材料检测与评价北京市重点实验室,北京100095

出　　处：《航空材料学报》2018年第3期58-64,共7页Journal of Aeronautical Materials

基　　金：国家自然基金项目(51341001);国家重点研发计划(2017YFB0702004)

摘　　要：研究[001]晶体取向的第二代单晶镍基高温合金DD6中温段下的低循环疲劳行为,实验温度为600℃,650℃,700℃和760℃,应变比为–1。结果表明:在此温度范围内,合金呈现循环硬化特性;随着温度的升高,[001]晶体取向DD6合金的弹性模量有所降低,合金的应变-寿命关系与温度相关。采用考虑温度影响修正的循环损伤累积(CDA)模型对[001]晶体取向DD6合金在中温段下的低循环疲劳寿命进行统一预测,预测寿命值位于实验结果的±3倍分散带以内。Low cycle fatigue （LCF） tests were conducted on a single crystal nickel-based superalloy DD6 with crystallographic orientations [001] at different elevated temperatures. The typical temperatures selected are 600 ℃, 650 ℃, 700 ℃ and 760 ℃, which represent the temperature field of turbine blade root or dovetail. The experimental results indicate that the characteristic of cyclic hardening exists in DD6 superalloy at middle temperature range. The LCF strain range-life curves are temperature-dependent. A modified cyclic damage accumulation （CDA） life prediction model is proposed. In this modified model, an approximate logarithmic linear function is introduced as the additional terms to consider the temperature effect. The prediction results are mainly distributed in scatter band of ±3. The temperature-modified CDA models agree well with the experimental data.

关 键 词：单晶镍基高温合金 低循环疲劳 中温段 寿命预测 

分 类 号：TG146.15[一般工业技术—材料科学与工程] V250.3[金属学及工艺—金属材料]