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Effect of Nugget Size on Tensile and Fatigue Strength of Spot Welded AZ31 Magnesium Alloy
ISSN: 0148-7191, e-ISSN: 2688-3627
Published April 12, 2010 by SAE International in United States
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Interest in magnesium, as the lightest engineering metal, has increased in the automotive industry as a result of requirements for lighter and cleaner vehicles. Resistance spot welding (RSW) is already the predominant mode of fabrication in this industry, and the fatigue of spot welded magnesium sheet must be studied.
In this study, the tensile and fatigue strength of resistance spot welded AZ31 Mg alloy was studied. Three sets of tensile shear spot welded specimens were prepared with different welding parameters to achieve different nugget sizes. Metallographic examination revealed grain size changes from the base material (BM) to heat affected zone (HAZ) to the fusion zone (FZ). Monotonic tensile and fatigue tests were conducted and the effect of nugget size on tensile shear and fatigue strength was discussed. Modes of failure in each set of specimens under tensile and cyclic loading were examined and compared with those in steel and aluminum spot welds which are the most common materials in the automotive industry. Microstructural features of the fracture surface were studied.
CitationBehravesh, B., Liu, L., Jahed, H., Lambert, S. et al., "Effect of Nugget Size on Tensile and Fatigue Strength of Spot Welded AZ31 Magnesium Alloy," SAE Technical Paper 2010-01-0411, 2010, https://doi.org/10.4271/2010-01-0411.
Advances In Light Weight Materials – Aluminum, Casting Materials, and Magnesium Technologies, 2010
Number: SP-2294 ; Published: 2010-04-13
Number: SP-2294 ; Published: 2010-04-13
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