损伤力学方法在材料低周疲劳试验中的应用研究
Application research of damage dynamics for low cycle fatigue test
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摘要: 考察了低周疲劳过程中的弹性模量和应力随循环次数的变化.研究表明:可以用弹性模量和应力的变化来反映材料的低周疲劳损伤过程.对没有明显循环稳定阶段并表现为循环软化响应行为的材料, 不适合用应力的变化来定量的反映材料低周疲劳的损伤过程.用弹性模量随循环次数的演化关系得到了不同应变水平下材料的疲劳裂纹萌生寿命, 并用三参数幂函数方程对应变与疲劳裂纹萌生寿命进行了拟合处理, 得到了应变与疲劳裂纹萌生寿命方程.Abstract: The change of elastic modulus and stress associated with fatigue cyclic number was investigated during low cycle fatigue.The research shows that,the low cycle fatigue damage can be determined by the change of elastic modulus and stress.For the materials,which have no cyclic steady stage but exhibit cyclic softening,this method isn't suitable to determine the low cycle fatigue damage with the change of stress.The fatigue crack initiation life was acquired by the change of elastic modulus under different strain levels,so the relationship between strain and fatigue crack initiation life was determined by three parameters power equation.
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Key words:
- aerospace propulsion system /
- ultrasonic /
- elastic modulus /
- stress /
- damage /
- low cycle fatigue
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[1] 勒迈特 J 著.损伤力学教程[M].陶春虎,译.北京:科学出版社,1996. [2] 钟裴晖,王寅观,杨海涛,等.用超声波法测试20钢低周疲劳过程中弹性常数的变化[J].金属学报,2002,38(3):334-336.ZHONG Peihui,WANG Yinguan,YANG Haitao,et al.The change of elastic constant of steel 20 in low-cycle fatigue procedure measured by ultrasonic[J].Acta Metallurgica Sinica,2002,38(3):334-336. [3] Szilard J.Ultrasonic testing:non-conventional testing techniques[M].New Jersey:John Wiley & Sons Ltd.,1982. [4] Buck O.Harmonic generation for measurement of internal stress as produced by dislocations[J].IEEE Trans Sonics Ultrasonic,1976,SU-23:346-350. [5] Buck O,Alers G A.New techniques for detection and monitoring of fatigue damage[J].Fatigue and Microstructure American Society for Metals,1979,101-147. [6] 徐从元,姜文华.疲劳金属材料非线性声学特性的实验研究[J].南京大学学报,2000,36(3):328-335.XU Congyuan,JIANG Wenhua.Experimental investigation on acoustic nonlinearity of fatigued metals[J].Journal of Naijing University,2000,36(3):328-335. [7] Jhang K Y,Kim K C.Evaluation of material degradati-on using nonlinear acoustic effect[J].Ultrasonic,1999,37:39-44. [8] Kang J,Qu J,Saxena A,et al.On the detection of creep damage in a directionally solidified Nickel base superalloy using nonlinear ultrasound[C]∥In:Thompson D O,Chimenti D E,eds.Review of progress in quantitative nondestructive evaluation.New York:American Institute of Physics,2004,23:1248-1255. [9] Hirsekorn S.Nonlinear transfer of ultrasound by adhes-ive joints-a theoretical Description[J].Ultrasonics,2001,39:57-68. [10] 税国双,汪越胜,曲建民.材料力学性能退化的超声无损检测与评价[J].力学进展,2005,35(1):52-68.SHUI Guoshuang,WANG Yuesheng,QU Jianmin.Advances in nondestructive test and evaluation of material degradation using nonlinear ultrasound[J].Advances In Mechanics,2005,35(1):52-68.
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