Crack Closure Behavior and Crack Propagation Characteristic of FGH95 Powder Metallurgy Superalloy
ZUO Ping1,2, WEI Da-sheng1,2, WANG Yan-rong1,2
1. School of Energy and Powder Engineering, Beihang University, Beijing 100191, China;
2. Co-Innovation Center for Advanced Aero-Engine, Beijing 100191, China
Abstract：Plasticity-induced crack closure effect of compact tension (CT) specimen of FGH95 powder metallurgy superalloy was investigated by using finite element method. The stress distribution in crack surface was analyzed. The effects of three principal factors, the constitutive model, mesh density and stress ratio, on the crack closure behavior were studied, to further establish crack propagation life analysis model of CT specimens with considering crack closure, and to predict life. The results show that crack closure in elastic-perfectly plastic constitutive model appears more sensitive to grid cell than that in multi-linear kinematic hardening constitutive model. Crack closure trends to be stable with the number of crack tip elements in the plastic zone reach to 20. Crack closure decreases with the increase of stress ratio, and disappears as stress ratio reaches to 0.5. The revised life prediction model shows higher prediction accuracy than traditional model for CT specimens.
[1] ELBER W. Fatigue crack closure under cyclic tension[J].Engineering Fracture Mechanics,1970,2(1):37-45.
[2] GONZALEZ-HERRERA A,ZAPATERO J. Influence of minimum element size to determine crack closure stress by the finite element method[J].Engineering Fracture Mechanics,2004,72(3):337-355.
[3] SOLANKI K, DANIEWICZS R, NEWMAN J C. Finite element analysis of plasticity-induced fatigue crack closure: an overview[J].Engineering Fracture Mechanics,2005,71(2):149-171.
[4] JIANG Yan-yao,FENG Miao-lin, DING Fei. A reexamination of plasticity-induced crack closure in fatigue crack propagation[J]. International Journal of Plasticity,2004,21(9):1720-1740.
[5] 陈勇,宋迎东,高德平. FGH95 粉末高温合金裂纹闭合数值模拟[J].材料科学与工程学报,2004,22(3):347-350.CHEN Yong, SONG Ying-dong, GAO De-ping.Numerical simulation of crack closure in FGH95 powder metallurgy superalloys[J]. Journal of Materials Science & Engineering,2004,22(3):347-350.
[6] HOU C Y. Three-dimensional finite element analysis of fatigue crack closure behavior in surface flaws[J]. International Journal of Fatigue,2004,26(11):1225-1239.
[7] NEWMAN J C, WU X R, ZHAO W, et al.Small crack growth and fatigue life prediction for high-strength aluminum alloys: part I-experimental and fracture mechanics analysis[J].Fatigue and Fracture of Engineering Materials and Structures,1998,21(11): 1289-1306.
[8] NEWMAN J C, WU X R, SWAIN M H, et al. Small crack growth and fatigue life prediction for high-strength aluminum alloys: part II-crack closure and fatigue analysis[J].Fatigue and Fracture of Engineering Materials and Structures,2000,23(1):59-72.
[9] SOLANKI K, DANIEWICZ S R, NEWMAN J C. A new methodology for computing crack opening values from finite element analyses[J].Engineering Fracture Mechanics,2003,71(7):1165-1175.
[10] 陈亚龙,杨晓光. 带保载平面应变塑性诱发裂纹闭合效应[J].航空动力学报,2010,25(9):2030-2035. CHEN Ya-long,YANG Xiao-guang. Plasticity-induced fatigue crack closure under plane strain condition with dwelling[J].Journal of Aerospace Power,2010,25(9):2030-2035.
[11] McCLUNG R C, SEHITOGLU H. On the finite element analysis of fatigue crack closure-1.basic modeling issues[J].Engineering Fracture Mechanics,1989,33(2):237-252.
[12] BLANDFORD R S,DANIEWICZ S R,SKINN ER J D. Determination of the opening load for a growing crack: evaluation of experimental data reduction techniques and analytical models[J]. Fatigue Fract Eng Mater Struct,2002,25(1):17-26.
[13] PARIS P C, ERDOGAN F. A critical analysis of crack propagation laws[J]. Journal of Basic Engineering Transaction of the ASME,1963,85:528-534.
[14] 魏大盛,王延荣.粉末冶金涡轮盘裂纹扩展特性分析[J].推进技术,2008,12(6):753-758. WEI Da-sheng,WANG Yan-rong. Lifing methodology of crack propagation in powder metallurgy turbine disk[J].Journal of Propulsion Technology,2008,12(6):753-758.
2015, Vol. 43 
