Experimental test and simulation calculation of fatigue properties of aluminum–titanium-steel explosive welded connector under tension-compression cyclic loading

Abstract

The three-layer clad plate (aluminum alloy layer/commercial pure titanium layer/CCSB steel layer) was prepared by explosive welding as marine transition connector. The fatigue properties of clad plate were studied by experiment and finite element simulation. The fatigue limit and S–N curve were obtained by axial high-cycle fatigue test under tension-compression loading. The up-and-down method and group method were used respectively. Combining Static Structural module and DesignLife module based on the ANSYS Workbench Platform, the stress distribution, safety factor and fatigue life of clad plate under different loads were calculated. The results show that fatigue limit of Al–Ti-steel clad plate is 55 MPa, and the fatigue fracture mainly occurs in the 104∼106 cycles period in the stress range of 65 MPa∼100 MPa. The maximum relative error of fatigue life is 7.05%, and the relative error of fatigue limit is 0.45% between model and test fitting values. The results of finite element simulation have good agreement with the results of experimental method, which proves the feasibility and reliability of finite element simulation to analyze and forecast fatigue property of explosive welded clad plate. The position of the stress concentration is at the connection part between steel and pure titanium, while fatigue fracture occurs in the 3003 aluminum alloy layer because of the low tensile strength. Improving the tensile strength of Al-steel joint material is a key measure for solving the fracture problem of hull foundation.