MS Thesis: In-Situ Manufacturing Processes for Aluminum Matrix Nanocomposites

Wednesday, December 19, 2018
1:00 pm to 3:00 pm
Floor/Room #: 

Increasing the mechanical properties of cast aluminum components at temperatures in the vicinity of 300°C will allow for lightweighting opportunities, especially in automotive and aerospace applications. Metal-matrix nanocomposites (MMNCs) show great promise in this regard, in the form of aluminum as a matrix containing well-dispersed ceramic nanoparticles. These have been shown to retain most of the ductility of the matrix alloy, while adding strength and stiffness at far lower reinforcement fractions than are required in microcomposites. Unfortunately, MMNCs are plagued by issues which limit commercialization, such as high costs of production, issues with particle wetting and dispersion, low potential for scalability and poor castability. In this work, two existing MMNC manufacturing processes showing promise to overcome some of these obstacles were developed further: the in-situ gas-liquid reaction (ISGR) and self-propagating high-temperature synthesis (SHS). Composites with AlN and TiC reinforcements were produced, alloyed with several matrix compositions and squeeze cast. Insights into the effects of process design on microstructure and properties were gained, and potential process improvements and areas to focus future research were identified.