Influence of Single Peak Overload on Crack Closure Effect of CT Specimens Using Commercial Pure Titanium

doi:10.3901/JME.2021.12.169

Abstract

Abstract: Based on the digital image correlation technology, a nonlinear iterative method is used to fit the surface displacement field of the industrial pure titanium CT sample, so as to obtain the law of the crack tip position changing with the load before, during, and after overload. The crack opening displacement is obtained using the digital image correlation technology, the crack opening force is measured by the indirect method, and then the influence of overload on crack closure effect is studied. Comparing the strain field near the crack tip in the unloaded state between the cycle before overload and the cycle during overload, combined with the variation of the crack tip position with load and the crack opening force corresponding to the cycle, the analysis shows that the overload causes a large plastic deformation in the region near the crack tip, which is remained to a large extent even after unloading, resulting the weakening of the crack closure effect. As a result, the change of the crack tip position with the load after the overload is obviously different from that before the overload, and there is no obvious turning point in the force-displacement curve.

Key words: overload, crack closure, crack opening force, digital image correlation technology

CLC Number:

O346

YANG Bing, WEI Zhanjiang, LIAO Zhen, XIAO Shoune, YANG Guangwu, ZHU Tao, WANG Mingmeng, DENG Yongquan. Influence of Single Peak Overload on Crack Closure Effect of CT Specimens Using Commercial Pure Titanium[J]. Journal of Mechanical Engineering, 2021, 57(12): 169-178.

References

[1] ELBER W. Fatigue crack closure under cyclic tension[J]. Engineering Fracture Mechanics, 1970, 2(1):37-45.
[2] ELBER W. The significance of fatigue crack closure[J]. Damage Tolerance in Aircraft Structures, ASTM STP 486, American Society for Testing and Materials, 1971:230-242.
[3] SCHIJVE J, BROEK D. Crack propagation:the results of a test programme based on a gust spectrum with variable amplitude loading[J]. Aircraft Engineering and Aerospace Technology, 1962, 34(11):314-316.
[4] BATHIAS C, VANCON M. Mechanisms of overload effect on fatigue crack propagation in aluminium alloys[J]. Engineering Fracture Mechanics, 1978, 10(2):409-424.
[5] TOPPER T H, YU M T. The effect of overloads on threshold and crack closure[J]. International Journal of Fatigue, 1985, 7(3):159-164.
[6] VARDAR Ö. Effect of single overload in FCP[J]. Engineering Fracture Mechanics, 1988, 30(3):329-335.
[7] TOKAJI K, ANDO Z, KOJIMA T. Fatigue crack retardation of low carbon steel in saltwater[J]. Journal Engineering Materials and Technology (United States), 1984, 106, 1(1):38-42.
[8] SHIN C S, FLECK N A. Fatigue and fracture of a zinc die casting alloy[J]. International Journal of Fatigue, 1989, 11(5):341-346.
[9] 李年, 杜百平, 王章忠. 近门坎区Ⅰ, Ⅱ, Ⅲ型过载对Ⅰ型疲劳裂纹扩展延滞的影响-2.延滞机制[J]. 机械强度, 1997, 19(2):47-50. LI Nian, DU Baiping, WANG Zhangzhong. Influence of mode I, II and III overloading on the fatigue crack propagation of mode I in the near fatigue threshold region (2)[J]. Journal of Mechanical Strength, 1997, 19(2):47-50.
[10] MCEVILY A J, ISHIHARA S. On the retardation in fatigue crack growth rate due to an overload:A review[J]. SAE Brasil-International Congress on Fatigue, 2001, 1(4050):145-150.
[11] 雷贝贝. 拉伸超载作用下铝合金疲劳裂纹扩展特性及断裂机理研究[D]. 西安:长安大学, 2018. LEI Beibei. Study on fatigue crack growth behavior and fracture mechanism of Al-alloy subjected to tensile overloads[D]. Xi'an:Chang'an University, 2018.
[12] LU Y C, YANG F P, CHEN T. Effect of single overload on fatigue crack growth in QSTE340TM steel and retardation model modification[J]. Engineering Fracture Mechanics, 2019, 212:81-94.
[13] CHEN R, ZHU M L, XUAN F Z, et al. Near-tip strain evolution and crack closure of growing fatigue crack under a single tensile overload[J]. International Journal of Fatigue, 2020, 134:1-10.
[14] NOWELL D, MATOS P F P D. Application of digital image correlation to the investigation of crack closure following overloads[J]. Procedia Engineering, 2010, 2(1):1035-1043.
[15] NOWELL D, PAYNTER R J H, MATOS P F P D. Optical methods for measurement of fatigue crack closure:moiré interferometry and digital image correlation[J]. Fatigue & Fracture of Engineering Materials & Structures, 2010, 33(12):778-790.
[16] CHEN C Y, YE D Y, ZHANG L, et al Effects of tensile/compressive overloads on fatigue crack growth behavior of an extra-low-interstitial titanium alloy[J]. International Journal of Mechanical Sciences, 2016, 118:55-66.
[17] CHEN C Y, YE D Y, ZHANG L, et al. DIC-based studies of the overloading effects on the fatigue crack propagation behavior of Ti-6Al-4V ELI alloy[J]. International Journal of Fatigue, 2018, 112:153-164.
[18] LOPEZ-CRESPO P, MOSTAFAVI M, STEUWER A, et al. Characterisation of overloads in fatigue by 2D strain mapping at the surface and in the bulk[J]. Fatigue & Fracture of Engineering Materials & Structures, 2016, 39(8):1040-1048.
[19] 李晓宇. 单个拉伸过载情况下金属材料疲劳裂纹扩展行为的研究[D]. 合肥:合肥工业大学, 2015. LI Xiaoyu. Research on fatigue crack propagation behavior under a single tensile overload[D]. Hefei:Hefei University of Technology, 2015.
[20] 丁振宇, 高增梁, 王效贵. 16MnR钢过载峰作用下的疲劳裂纹扩展行为研究[J]. 机械工程学报, 2013, 49(16):84-90. DING Zhenyu, GAO Zengliang, WANG Xiaogui. Study on crack growth behavior of 16MnR subjected to single tensile overload[J]. Journal of Mechanical Engineering, 2013, 49(16):84-90.
[21] 韩瑾, 杨平, 董琴. 过载对于疲劳裂纹闭合效应的研究[J]. 武汉理工大学学报, 2017, 41(5):854-858. HAN Jin, YANG Ping, DONG Qin. Research of overload on fatigue crack closure effect[J]. Journal of Wuhan University of Technology, 2017, 41(5):854-858.
[22] BAPTISTA J B, ANTUNES F V, CORREIA L, et al. A numerical study of the effect of single overloads on plasticity induced crack closure[J]. Theoretical and Applied Fracture Mechanics, 2017, 88:51-63.
[23] WILLIAMS M L. On the stress distribution at the base of a stationary crack[J]. Journal of Applied Mechanics, 1957, 24(1):109-114.
[24] 范天佑. 断裂力学基础[M]. 北京:科学出版社, 2003. FAN Tianyou. Fundamentals of fracture mechanics[M]. Beijing:Science Press, 2003.
[25] VASCO-OLMO J M, JAMES M N, CHRISTOPHER C J, et al. Assessment of crack tip plastic zone size and shape and its influence on crack tip shielding[J]. Fatigue & Fracture of Engineering Materials & Structures, 2016, 39(8):969-981.
[26] 张蕊, 贺玲凤. 数字图像相关法测量聚碳酸酯板应力强度因子[J]. 工程力学, 2012, 29(12):22-27. ZHANG Rui, HE Lingfeng. Evaluating stress intensity factor of polycarbonate using digital image correlation[J]. Engineering Mechanics, 2012, 29(12):22-27.
[27] 杨冰, JAMES M N. 基于CJP模型的疲劳裂纹扩展率曲线及应用方法[J]. 机械工程学报, 2018, 54(18):76-84. YANG Bing, JAMES M N. Fatigue crack growth rate on the CJP model and its application method[J]. Journal of Mechanical Engineering, 2018, 54(18):76-84.
[28] VASCO-OLMO J M, DÍAZ F A, ANTUNES F V, et al. Plastic CTOD as fatigue crack growth characterising parameter in 2024-T3 and 7050-T6 aluminium alloys using DIC[J]. Fatigue & Fracture of Engineering Materials & Structures, 2020, 43(8):1-12.
[29] 王德人. 非线性方程组解法与最优化方法[M]. 北京:人民出版社, 1979. WANG Deren. Solutions and optimization methods of nonlinear equations[M]. Beijing:People's Publishing House, 1979.
[30] 董耀锋. C35钢疲劳裂纹张开力的确定方法研究[D]. 上海:上海交通大学, 2014. DONG Yaofeng. Research on methods for fatigue crack opening load determination in C35 steel[D]. Shanghai:Shanghai Jiao Tong University, 2014.
[31] KUJAWSKI D, STOYCHEV S. Parametric study on the variability of opening load determination[J]. International Journal of Fatigue, 2003, 25(9-11):1181-1187.
[32] 肖赢. 裂纹过载迟滞机理与实验研究[D]. 长沙:湖南大学, 2019. XIAO Ying. Mechanism and experimental study of crack overload retardation[D]. Changsha:Hunan University, 2019.