| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 778224 | International Journal of Fatigue | 2014 | 9 Pages |
•The fatigue fracture behaviors of spot welded Q&P980 steels were investigated.•Tensile-shear specimens show fracture along the circumference or the width direction.•Cross-tension specimens show pullout failure or fracture along the width direction.•The fatigue cracks initiate in the heat affected zone and at the interface of sheets.•The fatigue property of spot weld is independent of base material.
Microstructural characterization, micro-hardness tests, tensile and fatigue tests of spot welded Q&P980 steel were performed using tensile-shear and cross-tension specimens. The hardness values of nugget and base material were measured to be 497 HV and 334 HV, respectively. It is found that the fatigue cracks in heat affected zone (HAZ) initiate at the interface between two sheets. The fatigue failure modes consist of the fracture along the circumference or along the direction of width for tensile-shear specimens and pullout or fracture along the direction of width for cross-tension specimens. It is also found that the fatigue properties of spot welded Q&P980 and DP780 specimens are approximately the same in the case of tensile-shear and cross-tension specimens.
