Fatigue strength evaluation of cross-tension spot weld joints of cold rolled mild steel sheet

Kim, Doo-Hwan; Kim, Ho-Kyung

doi:10.1016/j.matdes.2009.01.002

Cited by 11 publications

(8 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The majority of studies in fatigue of RSW with automobile applications have been on steel and aluminum alloys [16][17][18][19]. These studies can be categorized into four major groups: fatigue modeling, comparative studies (RSW vs. other joining processes), process optimization, and characterization.…”

Section: Introductionmentioning

confidence: 99%

Characterization of magnesium spot welds under tensile and cyclic loadings

2011

View full text Add to dashboard Cite

Resistance spot welds of a magnesium alloy were characterized in terms of microstructure, hardness and monotonic and cyclic properties. Microstructural features in base metal and different zones in the weld region were discussed and the mechanical behavior of spot welds in tensile-shear configuration was studied. Effects of welding parameters were investigated on the micro-and macroscale characteristics of magnesium spot welds. To this end, five sets of spot weld specimens were prepared, utilizing different welding parameters. The effect of cyclic loading was studied on microstructure and hardness of the base metal and the weld region, and it was shown that microstructural features do not change remarkably under cyclic loading. Fatigue crack initiation and propagation behavior was discussed for different specimen sets under both low and high cyclic loads. Fatigue cracks under high cyclic loading initiated close to the nugget edge, and decreasing the cyclic load nucleated the cracks farther from the nugget.The final publication is available at Elsevier via http://dx.doi.org/10.1016/j.matdes.2011.06.001 © 2011 ABSTRACTResistance spot welds of a magnesium alloy were characterized in terms of microstructure, hardness and monotonic and cyclic properties. Microstructural features in base metal and different zones in the weld region were discussed and the mechanical behavior of spot welds in tensile-shear configuration was studied. Effects of welding parameters were investigated on the micro-and macro-scale characteristics of magnesium spot welds. To this end, five sets of spot weld specimens were prepared, utilizing different welding parameters. The effect of cyclic loading was studied on microstructure and hardness of the base metal and the weld region, and it was shown that microstructural features do not change remarkably under cyclic loading. Fatigue crack initiation and propagation behavior was discussed for different specimen sets under both low and high cyclic loads. Fatigue cracks under high cyclic loading initiated close to the nugget edge, and decreasing the cyclic load nucleated the cracks farther from the nugget.

show abstract

Section: Introductionmentioning

confidence: 99%

Characterization of magnesium spot welds under tensile and cyclic loadings

2011

View full text Add to dashboard Cite

show abstract

“…7 The applied load amplitude per button for the coach-peel and cross-tension specimens was converted from the applied load amplitude divided by the number of buttons for comparative study. 9 From Fig. As shown in Fig.…”

Section: Fatigue Strength Of the Jointsmentioning

confidence: 93%

“…This trend is in good agreement with the static strength results and is similar to results regarding the fatigue strength of spot weld joints obtained in a previous study. 9 From Fig. 6, for the coach-peel specimen geometry, the load amplitude per button as a function of number of cycles can be expressed as P amp ¼ 517:3ÂN À0:19 f .…”

Section: Fatigue Strength Of the Jointsmentioning

confidence: 99%

Fatigue behaviour of clinched joints in a steel sheet

Kim

2014

Fatigue Fract Eng Mat Struct

View full text Add to dashboard Cite

Clinch joining has been used in sheet metal work owing to its simplicity and because it facilitates the joining dissimilar metal sheets. In this study, monotonic and fatigue tests were conducted using coach‐peel and cross‐tension type specimens to evaluate the fatigue strength of clinch joints in a cold‐rolled mild steel sheet. The monotonic experimental results reveal that the coach‐peel specimen exhibits the lowest monotonic strength among the three specimen configurations. The coach‐peel and cross‐tension specimen geometries exhibit very low fatigue ratios, compared with the tensile‐shear specimen. The maximum von Mises and principal stresses at the fatigue endurance limit are much higher than the engineering tensile strengths of the steel sheet used to determine the three specimen geometries. Compared with the effective stress and maximum principal stress, the Smith–Watson–Topper fatigue parameter can be used for an appropriate prediction of the current experimental fatigue life. With regard to the coach‐peel specimen geometry, all samples exhibit pull‐out failure mode in the fatigue testing range. However, for the cross‐tension specimen geometry, mixed (pull‐out and interface) and interface failure modes occurred, depending on the number of cycles to failure.

show abstract

“…Numerous researchers have proposed methods of estimating fatigue life under constant force conditions, which are based on the nominal stress, local strain, stress intensity factor and J ‐Integral . For example, Yuuki et al .…”

Section: Introductionmentioning

confidence: 99%

“…Numerous researchers have proposed methods of estimating fatigue life under constant force conditions, which are based on the nominal stress, 13,14 local strain, 15 stress intensity factor [16][17][18][19][20] and J-Integral. 21,22 For example, Yuuki et al 23 tried to arrange fatigue test results of shear-typed, cross tension-typed and peel-typed spotwelded joints applying the fracture mechanics process. He investigated application of the equivalent stress intensity factor range ΔΚ θmax , 24 which considered mixed mode condition because both modes I and II loading acted to the slit edge of the spot-welded joints.…”

Section: Introductionmentioning

confidence: 99%

Cumulative fatigue damage evaluations on spot‐welded joints using 590 MPa‐class automobile steel

Tanegashima

Ohara

Akebono

et al. 2015

Fatigue Fract Eng Mat Struct

View full text Add to dashboard Cite

A B S T R A C T This study focused on local strain behaviour near the slit edge of spot-welded joints, where the fatigue crack initiated, and investigated methods of evaluating cumulative fatigue damage. A method of evaluating local strain amplitude by following modified Goodman's law gave almost the same result as an evaluation approach based on the external force and provided reasonable result on general strength design. An approach based on Smith-Watson-Topper's equation was easy to evaluate cumulative fatigue damage compared with the method based on modified Goodman's law and gave a good agreement with a criterion of the modified Miner's rule.Keywords fatigue damage; lap joints; mean stress effects; random loading; spot weld.cumulative fatigue damage value f = frequency [Hz] f 1 = lower value of the frequency [Hz] f u = upper value of the frequency [Hz] M = division number on the power spectrum n = actual cyclic number [cycles] N = estimated fatigue life [cycles] N f = number of cycles to failure [cycles] P a = force amplitude [kN] P B = tensile strength of the spot welded joints [kN] P Goodman,a = equivalent force amplitude evaluated following the modified Goodman's law [kN] P max = maximum force [kN] P mean = mean force [kN] P min = minimum force [kN]R p = force ratio S = power spectrum density function T = time x(t) = extreme values simulated following the stationary Gaussian random process at a certain time t. δ = residual of ε estimation,a and ε Goodman,a [με] Δω = division width of the angular frequency ε a = strain amplitude [με] ε B = fracture ductility [με] ε estimation,a = strain amplitude estimated using the regression curve of fatigue test results [με] ε Goodman,a = equivalent strain amplitude evaluated following the modified Goodman's law [με] ε max = maximum strain [με] Correspondence: A. Sugeta.

show abstract

Fatigue strength evaluation of cross-tension spot weld joints of cold rolled mild steel sheet

Cited by 11 publications

References 10 publications

Characterization of magnesium spot welds under tensile and cyclic loadings

Characterization of magnesium spot welds under tensile and cyclic loadings

Fatigue behaviour of clinched joints in a steel sheet

Cumulative fatigue damage evaluations on spot‐welded joints using 590 MPa‐class automobile steel

Contact Info

Product

Resources

About