High-strength Aluminum Alloy Friction Stir Welding Mechanism And Technology Research

This article mainly aims at friction stir welding aluminum ally plate easily to the defects,research the friction stir welding alloy welding mechanism and single dual axle shoulder friction stir welding process.With 2219 aluminum alloy and 5 A06 aluminum alloy for mother materials in friction stir welding, By changing the welding process parameters, the effect of the parameters on weld appearance quality is studied, to seam joint microstructure analysis micro-hardness testing and mechanical test. In 2219 the aluminum alloy copper elements and 5 A06 of magnesium alloy elements as tracer elements, tracking the flow of plastic material, and the plastic metal flow field were portrayed.Friction stir welding of temperature field is studied with finite element analysis method. Welding heat production model of the friction stir welding is established, the finite element analysis with the experimental results were compared, finally tallies well. The fluid mechanics theory as a foundation, constructing plastic material flow model of the friction stir welding with the plastic material as high viscosity non-newtonian incompressible fluid. The simulation results show:In a horizontal, back side of the part of the plastic move forward, part of the plastic metal backward movement, in the advancing side all of the plastic moving forward. And in thickness direction, most of the plastic metal in the back side movement to the surface, a small plastic metal movement to the bottom; most of the plastic metal in the advancing side is in the direction toward the stir tool level sports, a handful of plastic metal move to the surface or the bottom. The single,dual axle shoulder friction stir welding technology are compared, the experiment is 6 mm thick material 7 A05 aluminum alloy. Microstructure,micro-hardness,mechanical properties of the two kind welding are compared. The result shows that:dual axle shoulder friction stir welding head tensile strength can achieve the mother material of 78%, but less than single shaft shoulder joint, can achieve single shaft shoulder joint strength of 86.2%.