摘要
研究了特定试验条件下,镍基单晶DD10取向偏离[001]的程度对其低周疲劳行为的影响。结果表明:取向偏离度对DD10合金的低周疲劳行为影响明显。疲劳寿命随取向偏离度的增加而明显降低,在同等偏离度下,晶体取向靠近[001]-[011]的合金低周寿命优于取向靠近[001]-[111]的合金;分析发现:不同取向偏离度合金DD10低周疲劳寿命的差异源于其每循环周次的可累计塑性变形的差异。另一方面,取向偏离度对疲劳总应力幅和塑性应变幅的影响却截然相反,但对疲劳裂纹萌生和扩展方式影响不大。
Low cycle fatigue （LCF） properties of a nickel-based single crystal （SX） superalloy DD10 with different orientation deviation angles from the [001] axis were investigated at 760 ℃ with an invariable total strain amplitude of 1.4%. Results reveal that the LCF behaviors of DD10 exhibit a strong orientation-depandence. The fatigue life decreases apparently with the increment of the orientation deviation angle. For specimens with the same orientation deviation angle from the [001] axis, those on the [001]-[011] boundary exhibit a longer fatigue life than ones on the [001]-[111] boundary. It is found that the orientation-dependence of fatigue life stems from the difference of accumulated plastic deformation per cycle. On the other hand, both of total stress amplitude and plastic strain amplitude show a reverse orientation-dependence compared with the fatigue life. However, the orientation deviation shows no influence on the model of fatigue crack initiation and subsequent propagation.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2018年第1期1-6,共6页
Rare Metal Materials and Engineering
基金
National Natural Science Foundation of China(51631008,51101160)
关键词
单晶高温合金
合金DD10
取向偏离
低周疲劳
single crystal superalloy
DDIO alloy
orientation deviation
low cycle fatigue
