PSI - Issue 17

Liting Shi et al. / Procedia Structural Integrity 17 (2019) 355–362

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8 Jidong Kang/ Structural Integrity Procedia 00 (2019) 000 – 000 formation of an IMC layer between the aluminum alloy and LCS sheets affected the fracture modes. A new formula was derived to calculate a critical weld nugget diameter, in tensile shear specimens, = 4 (1 − ) , where = ⁄ , and are the shear strengths of the HAZ and IMC layer, respectively, t is the thickness and ε is the thickness reduction ratio. , and were directly measured using newly developed shear and mini-shear tests. The prediction of fracture modes using the calculated critical weld nugget diameters for different stack-ups of aluminum to low carbon steel with different sheet thickness were in excellent agreement with the observed experimental fracture modes. Acknowledgements The authors gratefully acknowledge the financial support from the Canadian Federal Government Energy Innovation Program, General Motors Canada and Natural Resources Canada, CanmetMATERIALS. 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