Effect of Fe Content on the Microstructure and Tensile Properties of TC4 Alloy Fabricated by Laser Solid Forming

The effect of Fe content on the microstructure and tensile properties of TC4 alloy manufactured by laser solid forming was investigated. The analysis of microstructure evolution of samples during heat treatment process shows that Fe does not affect the microstructure of as-built samples which consists of coarse columnar beta grains in the longitudinal section, while after heat treatments the coarse columnar beta grains in the longitudinal section are transformed into fine columnar beta grains with increasing Fe content from 0.026 wt% to 0.18 wt%, suggesting the occurrence of recrystallization. The tensile strength of samples at room temperature after heat treatments is higher than the standard requirements for forging. The tensile strength parallel to building direction is improved with the increasing of Fe, while for the strength perpendicular to building direction is insensitive to Fe content.