Multiaxial fatigue strength evaluation of welded joints is a complex subject for engineering. Based on ⅡW multiaxial criterion, experimental data from published literatures were re-evaluated using notch stress approach. The results reveal that the uniaxial fatigue assessment S-N curve recommended by ⅡW is unfit for multiaxial fatigue. Whereas, the data points of proportional loading and non-proportional loading have good coincidence under notched stress system. The assessment result is dangerous when the number of cycles is in the range of 1×104 ~1×105, and it is too conservative over 1×105 times. Based on this, the S-N curve (FAT=430 MPa, m=5.8) with the probability of survival Ps=97.7% is proposed for both proportional and non-proportional loading. This work can provide useful references for fatigue life prediction of engineering welded structures.
HU Xin
,
YAN Renjun
,
SHEN Wei
,
HU Yaoyu
,
HE Feng
. Research on ⅡW multiaxial fatigue criterion based on notch stress approach[J]. Transactions of The China Welding Institution, 2019
, 40(7)
: 77
-81
.
DOI: 10.12073/j.hjxb.2019400185
[1] 刘刚,黄如旭,黄一.复杂焊接接头多轴疲劳强度评估的等效热点应力法[J].焊接学报, 2012, 33(6):10-14 Liu Gang, Huang Ruxu, Huang Yi. Equivalent hot spot stress approach for multiaxial fatigue strength assessment of complex welded joints[J]. Transactions of the China Welding Institution, 2012, 33(6):10-14
[2] 周张义,王雨舟,杨欣.基于不同应力法的焊接构架纵向角接头疲劳累积损伤评估[J].焊接学报, 2018, 39(8):18-22 Zhou Zhangyi, Wang Yuzhou, Yang Xin. Fatigue cumulative damage assessment of longitudinal fillet welded gusset in welded frame based on different stress approaches[J]. Transactions of the China Welding Institution, 2018, 39(8):18-22
[3] 王东坡,曹舒,邓彩艳.基于缺口应力法的场桥导轨焊接结构疲劳性能评估[J].焊接学报, 2016, 37(4):5-8 Wang Dongpo, Cao Shu, Deng Caiyan. Notch stess concepts for fatigue assessment of welded portal crane rail structure[J]. Transactions of the China Welding Institution, 2016, 37(4):5-8
[4] Radaj D, Sonsino C, Fricke W. Recent developments in local concepts of fatigue assessment of welded joints[J]. International Journal of Fatigue, 2009, 31(1):2-11.
[5] Sonsino C M, Fricke W, de Bruyne F, et al. Notch stress concepts for the fatigue assessment of welded joints-Background and applications[J]. International Journal of Fatigue, 2012, 34(1):2-16.
[6] Sonsino C. Multiaxial fatigue assessment of welded joints-recommendations for design codes[J]. International Journal of Fatigue, 2009, 31(1):173-187.
[7] Radaj D, Lazzarin P, Berto F. Generalised Neuber concept of fictitious notch rounding[J]. International Journal of Fatigue, 2013, 51(6):105-115.
[8] Sonsino C M. Multiaxial fatigue of welded joints under in-and out-of-phase local strains and stresses[J]. International Journal of Fatigue, 1995, 17(1):55-70.
[9] Amstutz H K, Störzel, Seeger T. Fatigue crack growth of a welded tube-flange connection under bending and torsional loading[J]. Fatigue&Fracture of Engineering Materials&Structures, 2010, 24(5):357-368.
[10] Bertini L, Frendo F, Marulo G. Effects of plate stiffness on the fatigue resistance and failure location of pipe-to-plate welded joints under bending[J]. International Journal of Fatigue, 2016, 90(6):78-86.
[11] Yousefi F, Witt M, Zenner H. Fatigue strength of welded joints under multiaxial loading:experiments and calculations[J]. Fatigue&Fracture of Engineering Materials&Structures, 2010, 24(5):339-355.
[12] Witt M, Zenner H. Multiaxial fatigue behaviour of welded flange-tube connections under combined loading. experiments and lifetime calculation[C]//In:5th International conference on biaxial/multiaxial fatigue and fracture, Cracow, Poland; 1997:421-434.
[13] Fricke W. Guideline for the fatigue assessment by notch stress analysis for welded structures[C]//Assembly of International Institute of Welding, 2008:1-133.
