Laser processing of aluminum-titanium-tailored blanks

In the aircraft industry, hybrid structures of titanium (high strength, stiffness and corrosion resistance) and aluminum alloys could offer an advantage in comparison to conventional materials, e.g. in fuselage areas. Due to demand from the aircraft industry for new material combinations based on commercially available and qualified materials, research into the thermal joining of dissimilar materials has been initiated. The use of the laser technique for joining aluminum-titanium-tailored blanks and structures offers some advantages compared with conventional thermal joining processes. The main goal is the control of intermetallic phase formation, which occurs during thermal joining of aluminum to titanium. Through locally restricted energy input and high joining speed, the thickness of these phases can be reduced to below 2 mu m. This results in good tensile strength and therefore in promising forming behavior of the tailored blanks. This paper presents a study for laser joining of aluminum-titanium in the butt joint configuration, including FEM simulation, process development, characterization of the seam morphology by optical and electron microscopy and mechanical properties. (c) 2004 Published by Elsevier Ltd.