Response surface study on production of explosively-welded aluminum-titanium laminates

Abstract

This research was undertaken to produce strong and stiff, aluminum-titanium, multi-layered composites (laminates) by explosive welding, for applications requiring light-weight. The purpose of lamination is to create a material with superior mechanical properties resulting from plastic deformation produced by shock wave passage throughout each layer and from the presence of the explosively welded interfaces. A response surface study was performed on these laminates to investigate the mechanical behavior of the laminates with changes in two characteristic variables, abundance of interfaces and volume percentage of the more ductile component. For this purpose, a total of eighteen laminates, nine of which were the basis of a central composite design, were produced. One-step welding of these laminates was achieved by explosives-introduced pressuring; the material was supported by thicker steel plates on both sides to reduce the harmful effects of detonation and to produce smooth top and bottom surfaces. Yield strength, ultimate tensile strength, and elongation data were collected from tensile tests. A second-order model was fitted and a three dimensional response surface was built to define the relationship among the mechanical properties (yield strength) of the laminates and two design variables. The fitted second-order model clearly shows that the mechanical properties of the laminates depend strongly on the relative amounts of the components but only weakly on the abundance of interfaces within the selected operability region.