| Driven by the demand of improved fuel consumption, the use of light weight materials such as high strength steels and aluminum alloys has received increased attention by the automotive industry. Although these light weight materials have shown promising in meeting the demand of weight reduction, joining of light weight materials is still a challenging issue. After several years of research and development, the conventional spot welding process still falls short of delivering successful results. Hybrid welding process, which uses two joining methods simultaneously to form a joint, becomes an attractive joining technique. In this study, several welding processes were evaluated for joining aluminum alloys and high strength steels. The welding processes evaluated include spot welding, adhesive bonding, rivet-adhesive hybrid bonding, and spot weld-adhesive hybrid bonding. The materials evaluated include 6061T4 aluminum alloy and DP600 high strength steel.;A finite element analysis (FEA) was employed to assess the quality and strength of welded structure. FEA results were validated using actual experimental test results. It was found that the weld-bonded and rivet-bonded aluminum welds exhibited a slightly lower static strength than the adhesive-bonded aluminum welds. However, the weld-bonded and rivet-bonded aluminum welds exhibited much higher strength than either the aluminum spot welds or the steel spot welds. A model centered on the concept of a damage parameter was proposed that successfully correlated the FEA results with the experimental results. Finally, advanced nondestructive testing was conducted. NDT results also correlated well with both FEA and experimental test results. |
