PSI - Issue 37

Liting Shi et al. / Procedia Structural Integrity 37 (2022) 351–358 L Shi et al/ Structural Integrity Procedia 00 (2022) 000 – 000

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The maximum principal strains are extracted at the front element of the root notch and compared for all models. This is consistent with Shi et al. (2020b).

Fig. 1 Finite element models of tensile shear specimens with asymmetric notch root angles (a) larger notch root angle in leading edge; (b) larger notch angle in trailing edge.

4. Results and discussion 4.1. Weld characterization

The macrostructures of the AA5754-HSLA RSWs are shown in Fig. 2a and Fig. 2b. No defects (e.g., gas porosity, shrinkage porosity, or cracking) were observed at the periphery of the aluminum weld nugget which is the joint load bearing region. The average weld nugget diameter of the positive and negative polarity RSWs was measured to be 7.9 mm and 7.5 mm, respectively. In addition, the average weld nugget diameter of AA5754-AA5754 RSWs was

Steel

Aluminum

Fig.2 Weld characterization of resistance spot welds of 1.1mm 5754-2.0mm HSLA (a) macrostructure of positive polarity; (b) macrostructure of negative polarity; (c) thickness measurements of intermetallic compounds (IMC); and (d) microhardness measurements.