Finite element modelling of the fatigue damage in an explosive welded Al-dual-phase steel

In this study, production of dual phase steel-Al 1100 aluminium alloy laminated composite by explosive welding and investigation the microstructural and mechanical properties especially fatigue life of the composite and its components were aimed. Finite element analysis (FEA) was used to simulate the bending fatigue tests of the Al 1100-DP steel (LITEC 1050) bimetal. A semi-wave at the explosive interface with intermetallic was obtained as a microstructural result. Hardness was increased near the interface due to deformation and intermetallic formation at the explosive weld interface. The impact test results showed that the samples' impact toughness was enriched by fabricating steel-Al laminated composite. The results also showed that the Al 1100-DP steel (LITEC 1050) bimetal composite properties were appropriate to the composite theory and satisfied strength-ductility relations accomplished. Additionally, the bending fatigue test and FEA results were compatible. Moreover, fatigue cracks were observed at the explosive weld interface between Litec DP steel and intermetallic but not at the Al-intermetallic interface.