Additive Manufacturing of Metal Matrix Composite Parts

Refractory metals in a matrix offer several advantages in part performance, including improved strength-to-weight ratio, high thermal conductivity, low thermal expansion coefficient, acoustic signature customization, and increased wear resistance.  In this study, Additive Friction Stir (AFS), a solid-state additive manufacturing process, has been used to additively manufacture Al-SiC with varying silicon carbide volume fractions.  Additionally, Al-W and Al-Mo MMCs with a high volume fraction of molybdenum and tungsten particles have been fabricated. Relatively homogenous wrought microstructures with refined grains and nearly uniform distribution of reinforcement particles were developed via AFS. AM parts are fully dense and do not require a secondary densification process.  The detailed microstructure, hardness and tensile properties will be reviewed to identify the deposition quality and mechanical performance of the AFS created materials.