Microstructure and mechanical properties of electron beam freeform fabricated TiB2/Al-Cu composite

TiB2/ZL205 composite thin wall component was built with electron beam freeform fabrication by feeding TiB2/Al-Cu wire. The microstructure and mechanical properties were tested and studied. The main existed phases were alpha-Al, Al2Cu phases and TiB2 particles. The eutectic Al2Cu phase and TiB2 particles distributed mainly along the grain boundaries in alpha-Al matrix. The composite exhibited equiaxed grains, and the average grain size was 13.3 mu m. The hardness was about 71.8 HV. The ultimate tensile strength, yield strength and elongation of the samples in horizontal direction were 198 MPa, 88 MPa and 12.9%, respectively. The properties in vertical direction were slightly lower. (C) 2020 Elsevier B.V. All rights reserved.