A notch stress intensity approach to assess the multiaxial fatigue strength of welded tube-to-flange joints subjected to combined loadings

被引:172
作者
Lazzarin, P
Sonsino, CM
Zambardi, R
机构
[1] Univ Padua, Dept Management & Engn, I-36100 Vicenza, Italy
[2] Fraunhofer Inst Struct Durabil LBF, D-64289 Darmstadt, Germany
关键词
energy; equivalent stress; multiaxial fatigue; notch stress intensity factor; welded joint;
D O I
10.1111/j.1460-2695.2004.00733.x
中图分类号
TH [机械、仪表工业];
学科分类号
0802 ;
摘要
Full penetration butt weld joints between a tube and its flange are considered, subjected to pure bending, pure torsion and a combination of these loading modes. The model treats the weld toe like a sharp V-notch, in which mode I and mode III stress distributions are combined to give an equivalent notch stress intensity factor (N-SIF) and assess the high cycle fatigue strength of the welded joints. The N-SIF-based approach is then extended to low/medium cycle fatigue, considering fatigue curves for pure bending and pure torsion having the same slope or, alternatively, different slopes. The expression for the equivalent N-SIF is justified on the basis of the variation of the deviatoric strain energy in a small volume of material surrounding the weld toe. The energy is averaged in a critical volume of radius R-C and given in closed form as a function of the mode I and mode III N-SIFs. The value of R-C is explicitly referred to high cycle fatigue conditions, the material being modelled as isotropic and linear elastic. R-C is thought of as a material property, independent in principle of the nominal load ratio. To validate the proposal, several experimental data taken from the literature are re-analysed. Such data were obtained by testing under pure bending, pure torsion and combined bending and torsion, welded joints made of fine-grained Fe E 460 steel and of age-hardened AlSi1MgMn aluminium alloy. Under high cycle fatigue conditions the critical radius R-C was found to be close to 0.40 mm for welded joints made of Fe E 460 steel and close to 0.10 mm for those made of AlSi1MgMn alloy. Under low/medium cycle fatigue, the expression for energy has been modified by using directly the experimental slopes of the pure bending and pure torsion fatigue curves.
引用
收藏
页码:127 / 140
页数:14
相关论文
共 33 条
[1]  
[Anonymous], 1999, MULTIAXIAL FATIGUE
[2]   Fatigue strength of fillet welded structural steels: finite elements, strain gauges and reality [J].
Atzori, B ;
Meneghetti, G .
INTERNATIONAL JOURNAL OF FATIGUE, 2001, 23 (08) :713-721
[3]   From a local stress approach to fracture mechanics: a comprehensive evaluation of the fatigue strength of welded joints [J].
Atzori, B ;
Lazzarin, P ;
Tovo, R .
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES, 1999, 22 (05) :369-381
[4]   Stress field parameters to predict the fatigue strength of notched components [J].
Atzori, B ;
Lazzarin, P ;
Tovo, R .
JOURNAL OF STRAIN ANALYSIS FOR ENGINEERING DESIGN, 1999, 34 (06) :437-453
[5]  
ATZORI B, 1985, P 13 AIAS C BERG IT
[6]   A volumetric energy based high cycle, multiaxial fatigue citerion [J].
Banvillet, A ;
Palin-Luc, T ;
Lasserre, S .
INTERNATIONAL JOURNAL OF FATIGUE, 2003, 25 (08) :755-769
[7]   THE USE OF NOTCH STRESS INTENSITY FACTOR AS A FATIGUE-CRACK INITIATION PARAMETER [J].
BOUKHAROUBA, T ;
TAMINE, T ;
NIU, L ;
CHEHIMI, C ;
PLUVINAGE, G .
ENGINEERING FRACTURE MECHANICS, 1995, 52 (03) :503-512
[8]  
FROUSTEY C, 1992, TECHNOLOGY TRANSFER, P79
[9]  
Gough H., 1937, P I AUTOMOBILE ENG, V31, P821
[10]   PLANE ELASTOSTATIC ANALYSIS OF V-NOTCHED PLATES [J].
GROSS, B ;
MENDELSON, A .
INTERNATIONAL JOURNAL OF FRACTURE MECHANICS, 1972, 8 (03) :267-276