表面粗糙度对三维应力集中系数及疲劳寿命的影响

摘要/Abstract

摘要：

利用半椭圆微缺口表征表面粗糙度，建立了平板表面形貌的三维有限元模型，总结了微缺口参数对表面应力集中系数的影响规律。建立了表面应力集中系数与表面粗糙度之间的经验公式，预测了不同表面粗糙度下平板的疲劳寿命。研究结果表明：应力集中系数与表面粗糙度成正相关关系；当缺口数大于10时，应力集中系数随缺口数的增加而恒定；当间宽比大于5时，多缺口已经失去缓和应力集中的作用；疲劳寿命随着表面粗糙度的增加而缩短。

关键词: 表面粗糙度, 半椭圆微缺口, 应力集中系数, 疲劳寿命

Abstract:

According to building three dimensional finite element model of plate surface topography, whose surface roughness were represented as the semi-ellipse micro-notches, the influences of micro-notch parameters on surface stress concentration factors were summed up. Empirical equation that related surface roughness to surface stress concentration factors of plate was established and predicted the fatigue life of the plate under different surface roughnesses. Research results show that:it is positive between stress concentration factor and surface roughness; when the number of notch is over 10, stress concentration factor is constant with the increase of the number of notch; when the ratio is over 5, multi-notches have been out of action to lessen the stress concentration; when surface roughness increases, the fatigue life decreases.

Key words: surface roughness, semi-ellipse micro-notch, stress concentration factor, fatigue life

中图分类号:

廖智奇, 吴运新, 袁海洋. 表面粗糙度对三维应力集中系数及疲劳寿命的影响[J]. 中国机械工程, 2015, 26(2): 147-151.

Liao Zhiqi, Wu Yunxin, Yuan Haiyang. Influences of Surface Roughness on Three Dimensional Stress Concentration Factor and Fatigue Life[J]. China Mechanical Engineering, 2015, 26(2): 147-151.

参考文献

[1]Zahavi E,Torbilo V,Press S.Fatigue Design:Life Expectancy of Machine Parts[M].London:CRC Press,1996.
[2]张东初,裴旭明.加工工艺对表面粗糙度及疲劳寿命的影响[J]. 中国机械工程，2003,14(16):1374-1377.
Zhang Dongchu,Pei Xuming.Effects of Machining Processes on Surface Roughness and Fatigue Life[J].China Mechanical Engineering,2003,14(16):1374-1377.
[3]曾泉人,刘更,刘岚.机械加工零件表面完整性表征模型研究[J].中国机械工程, 2010,21(24):2995-2999.
Zeng Quanren,Liu Geng,Liu Lan.Quantitative Description Model of Surface Integrity for Machined Parts[J].China Mechanical Engineering,2010,21(24):2995-2999.
[4]裴旭明,陈五一,任炳义,等.加工工艺对7075铝合金紧固孔表面形貌和组织的影响[J].中国有色金属学报,2001,11(4)：655-660.
Pei Xuming,Chen Wuyi,Ren Bingyi,et al.Influence of Machining Processes on Surface Microphotograph and Microstructure of Fastening Holes[J].The Chinese Journal of Nonferrous Metals,2001,11(4): 655-660.
[5]岳珠峰.多晶体光滑表面疲劳微裂纹形核机理研究[J].应用数学和力学,2004,25(8)：809-814.
Yue Zhufeng.On the Study of the Initiation of the Micro Crack on the Smooth Surface of Polycrystalline[J]. Applied Mathematics and Mechanics,2004,25(8):809-814.
[6]Arola D,Williams C L.Estimating the Fatigue Stress Concentration Factor of Machined Surfaces[J].International Journal of Fatigue,2002,24(9):923-930.
[7]Andrews S,Sehitoglu H.A Computer Model for Fatigue Crack Growth from Rough Surfaces[J].International Journal of Fatigue,2000,22(7)：619-630.
[8]As S K,Kallerud B,Tveten B W,et al.Fatigue Life Prediction of Machined Components Using Finite Element Analysis of Surface Topography[J].International Journal of Fatigue,2005,27(10/12):1590-1596.
[9]章刚，刘军，刘永寿，等. 表面粗糙度对表面应力集中系数和疲劳寿命影响分析[J]. 机械强度，2010(1)：110-115.
Zhang Gang,Liu Jun,Liu Yongshou,et al.Effect of Roughness on Surface Stress Concentration Factor and Fatigue Life[J]. Journal of Mechanical Strength,2010(1):110-115.
[10]刘军,刘勇俊,刘永寿,等.开孔试件的表面粗糙度对疲劳寿命影响的定量分析[J].中国机械工程,2008,19(3):327-329.
Liu Jun,Liu Yongjun,Liu Yongshou,et al.Quantitative Analysis of Roughness Effect on Fatigue Life of Specimen with Open Holes[J].China Mechanical Engineering,2008,19(3):327-329.
[11]王启智,戴峰.拉伸半无限圆孔板应力集中系数研究[J].四川大学学报(工程科学版),2002,34(4):5-9.
Wang Qizhi,Dai Feng.A Study of Stress Concentration Factors for Tension Semi-infinite Plate with a Circular Hole[J]. Journal of Sichuan University(Engineering Science Edition),2002,34(4):5-9.
[12]王元清,武延民,王晓哲,等.含缺口受拉平板三维应力场及其对脆性破坏的影响[J].清华大学学报(自然科学版), 2002, 42(6): 832-834.
Wang Yuanqing,Wu Yanmin,Wang Xiaozhe,et al.3-D Stresses in a Flat Slab with a Crack in Tension and the Effect on Brittle Fracture[J].Journal of Tsinghua University (Sci & Tech),2002,42(6)：832-834.
[13]西田正孝.应力集中[M].李安定,译.北京:机械工业出版社,1986.
[14]黄伯云，邱冠周. 有色金属材料手册[M]. 北京：化学工业出版社，2009.
[15]郑修麟. 金属疲劳的定量理论[M]. 西安：西北工业大学出版社，1994.