The objective of this project is to advance the fundamental understanding of the Laser Additive Manufacturing processes that is necessary for the industrial implementation of LAM in a wide range of aerospace applications. LAM combines characteristics of conventional laser welding with the ability to automatically produce complex geometries. One goal of LAM is to reduce the cost of manufacturing new aerospace components with complex features. In conventional manufacturing methods, complex features must be incorporated into a casting or forging process, at substantial cost. Cost savings can be realized by using LAM to add complex features to easy-to-produce, generic manufactured components. Other applications of LAM include the repair of worn or cracked components by selective material addition, which is substantially more economical than part replacement. In this project, the relationship between deposition process variables and the three key deposit characteristics critical to aerospace applications: melt pool size, residual stress and microstructure will be developed. This understanding will be demonstrated through model results presented in the form of process maps, which "map out" the dependence of deposit characteristics on process variables such as laser power and laser velocity. Process maps will be of direct use to industry researchers working to advance LAM processes. This research establishes a strong collaborative team including academic researchers from three universities, government researchers from two national labs, and several industry partners. The results of this work are expected to have a significant impact on the widespread industrial implementation of LAM processes. This project will also expose graduate, undergraduate and high school students to research integrating aerospace applications and manufacturing constraints with the fundamentals of solid mechanics, heat transfer and materials science.
