Effect of powder heat treatment and post heat treatment on the mechanical properties of cold sprayed AA7050

In this presentation, we will discuss the application of heat treatment, in two distinct ways, to enhance the mechanical properties of cold sprayed AA7050 material. Cold spray deposition for repair applications of Al alloy components has recently shown promising results. One of the key challenges is to achieve mechanical properties comparable to wrought material. In particular, cold spray deposited materials can exhibit low ductility. In this work, as-atomized and solutionized AA7050 powders were cold sprayed. The powder heat treatment enhances the mechanical properties of the material by dissolving the intermetallic networks present in the as-atomized powders. In another approach, a series of post-deposition heat treatments were performed to simulate artificial aging. Cold sprayed deposits formed from both powders were solutionized for 1h at 480˚C and then aged at 120˚C for different dwell times. The hardness data suggests that the aging kinetics are accelerated compared with wrought materials, which can be associated with the high defect density. Detailed electron microscopy and mechanical testing of the cold spray materials are being performed to correlate strength and ductility with changes in the micro and nanostructures of the cold sprayed materials. We will also compare these results with similar studies on cold sprayed AA7075.