Designing high-temperature oxidation-resistant titanium matrix composites via directed energy deposition-based additive manufacturing

Composite material development via laser-based additive manufacturing offers many exciting advantages to manufacturers; however, a significant challenge exists in our understanding of processproperty relationships for these novel materials. Herein we investigate the effect of input processing parameters towards designing an oxidation-resistant titanium matrix composite. By adjusting the linear input energy density, a composite feedstock of titanium-boron carbide-boron nitride (5 wt% overall reinforcement) resulted in a highly reinforced microstructure composed of borides and carbides and nitrides, with variable properties depending on the overall input energy. Crack-free titanium-matrix composites with hardness as high as 700 +/- 17 HV0.2/15 and 99.1% relative density were achieved, with as high as a 33% decrease in oxidation mass gain in the air relative to commercially pure titanium at 700 degrees C for 50 h. Single-tracks and bulk samples were fabricated to understand the processing characteristics and in situ reactions during processing. Our results indicate that input processing parameters can play a significant role in the oxidation resistance of titanium matrix composites and can be exploited by manufacturers for improving component performance and high temperature designs. (C) 2021 The Author(s). Published by Elsevier Ltd.

Automated summary

Through adjusting input processing parameters, a oxidation-resistant titanium matrix composite with reinforced microstructure composed of borides, carbides, and nitrides was successfully developed, showing improved hardness and oxidation resistance compared to commercially pure titanium.