基于临界距离理论的TC4合金缺口试样 低循环疲劳寿命预测

辛朋朋; 胡绪腾; 宋迎东

基于临界距离理论的TC4合金缺口试样低循环疲劳寿命预测

南京航空航天大学能源与动力学院机械结构力学及控制国家重点实验室, 南京 210016

基金项目: 基础科研计划; 南京航空航天大学基本科研业务费专用科研项目(NS2010038)

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出版历程
- 收稿日期: 2011-06-09
- 刊出日期: 2012-05-28

LCF life prediction for TC4 alloy notched specimens based on theory of critical distance

State Key Laboratory of Mechanics and Control of Mechanical Structures, College of Energy and Power Engineering, Nanjing University of Aeronautics and Astroncsutics, Nanjing 210016, China

摘要

摘要: 对TC4合金缺口试样的临界距离和低循环疲劳寿命分别进行了分析和预测.研究了缺口临界距离与疲劳寿命、载荷比、应力集中系数的相关关系及其对寿命预测结果的影响.研究结果表明:TC4合金缺口试样的临界距离不仅与疲劳寿命有关,还与载荷比和应力集中系数相关.载荷比相同时,临界距离与疲劳寿命之间可采用幂函数经验公式来描述.载荷比为-1和0.1时,TC4合金缺口试样的临界距离-疲劳寿命曲线基本重合,当载荷比增大为0.5时,临界距离明显增大.载荷比和疲劳寿命相同时,临界距离与应力集中系数近似成反比关系.寿命预测结果表明:采用临界距离理论预测TC4合金缺口疲劳寿命时,要获得更准确的疲劳寿命预测结果,应同时考虑临界距离与疲劳寿命、载荷比以及应力集中系数等因素的相关性.
- 缺口 /
- 低循环疲劳 /
- 寿命预测 /
- 临界距离理论 /
- Walker等效应变
Abstract: Low cycle fatigue (LCF) life prediction and critical distance analysis for TC4 alloy notched specimens were conducted.The correlation between the critical distance and fatigue life,load ratio,stress concentration factor and their influence on the fatigue life prediction were studied.The result suggests that the critical distance of TC4 alloy is not only related to the fatigue life,but also to the load ratio and stress concentrate factor.For the same load ratio,the power function can be used to describe the relationship between the critical distance and the fatigue life.For TC4 alloy notched specimens,when the load ratios were -1 and 0.1,the critical distance-fatigue life curves almost coincide;when the load ratios rose up to R=0.5,the critical distance increased obviously.For the same load ratio and fatigue life,the critical distance of TC4 alloy notched specimens was approximately inverse to the stress concentrate factor.Life prediction results show that the correlation between critical distance and fatigue life,load ratio,stress concentration factor must be considered to obtain more accurate fatigue life prediction for notched TC4 alloy using the theory of critical distance.
- notch /
- low cycle fatigue /
- life prediction /
- theory of critical distance /
- Walker equivalent strain

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参考文献(15)

[1]	Neuber H.Theory of notch stresses:principles for exact calculation of strength with reference to structural form and material[M].2nd ed.Berlin:Springer-Verlag,1958.
[2]	Peterson R E.Notch sensitivity[M].Metal Fatigue,New York:McGraw Hill,1959:293-306.
[3]	Taylor D.The theory of critical distances:a new perspective in fracture mechanics[M].Oxford:Elsevier,2007.
[4]	Taylor D.Geometrical effects in fatigue:a unifying theoretical model[J].International Journal of Fatigue,1999,21(5):413-420.
[5]	Susmel L.The theory of critical distances:a review of its applications in fatigue[J].Engineering Fracture Mechanics,2008,75(7):1706-1724.
[6]	Taylor D,Bologna P,Knani K B.Prediction of fatigue failure location on a component using a critical distance method[J].International Journal of Fatigue,2000,22(9):735-742.
[7]	Susmel L,Taylor D.A novel formulation of the theory of critical distances to estimate lifetime of notched components in the medium-cycle fatigue regime[J].Fatigue & Fracture of Engineering Materials & Structures,2007,30(7):567-581.
[8]	Susmel L,Taylor D.An elasto-plastic reformulation of the theory of critical distances to estimate lifetime of notched components failing in the low/medium-cycle fatigue regime[J].Journal of Engineering Materials and Technology,2010,132(2):021002(8 pages).
[9]	Yamashita Y,Ueda Y,Kuroki H,et al.Fatigue life prediction of small notched Ti-6Al-4V specimens using critical distance[J].Engineering Fracture Mechanics,2010,77(9):1439-1453.
[10]	YANG Xiaoguang,WANG Jingke,LIU Jinlong.High temperature LCF life prediction of notched DS Ni-based superalloy using critical distance concept[J].International Journal of Fatigue,2011,33(11):1470-1476.
[11]	Lanning D B,Nicholas T,Haritos G K.On the use of critical distance theories for the prediction of the high cycle fatigue limit stress in notched Ti-6Al-4V[J].International Journal of Fatigue,2005,27(1):45-57.
[12]	Walker K.The effects of stress ratio during crack propagation and fatigue for 2024-T3 and 7075-T6 aluminum:effect of environment and complex load history on fatigue life.West Conshohocken:American Society Testing and Materials,STP 462,1970.
[13]	Jaske C E,Feddersen C E,Davis K B,et al.Analysis of fatigue,fatigue crack propagation,and fracture data.NASA-CR-132332,1973.
[14]	王卫国.轮盘低循环疲劳寿命预测模型和试验评估方法研究.南京:南京航空航天大学,2006. WANG Weiguo.Research on prediction model for disk LCF life and experiment assessment methodology.Nanjing:Nanjing University of Aeronautics and Astronautics,2006.(in Chinese)
[15]	北京航空材料研究所.航空发动机设计用材料数据手册(第一册)[M].北京:中国航空发动机总公司,1990.