Heat treatment of Ti-6Al-4V alloy manufactured by laser-based powder-bed fusion: Process, microstructures, and mechanical properties correlations
Abstract
The present study comprehensively a investigates the correlations between the heat treatment process parameters (temperature, time, and cooling rate) with the microstructure and tensile properties of Ti-6Al-4V samples manufactured by laser-based powder-bed fusion (L-PBF) additive manufacturing process. Understanding these correlations results in better engineering of the microstructure to obtain a desirable combination of ductility and strength for different applications. The primary, secondary, and tertiary α' with β particles are seen in the microstructure of the as-built sample. The heat treatment at below β transus temperature (Tβ) shows a similar microstructure to the as-built samples with a considerable increment in elongation. Increasing temperature in the range of α + β region illustrates the formation of α + β lamellar structure (primary, and secondary α) with increasing elongation and decreasing tensile strength. While increasing temperature above Tβ deteriorates the mechanical properties due to increasing the thickness of α lath, increasing the time of annealing leads to increasing and then decreasing elongation. Increasing the cooling rate from furnace cooling to air cooling and finally to water quenching results in increasing yield strength and ultimate tensile strength and decreasing the elongation due to the microstructural features such as α', α, and β. Finally, the fractography of brittle and ductile samples is presented and correlated with the obtained microstructural and mechanical properties.
Publication Title
Journal of Alloys and Compounds
Recommended Citation
Etesami, S., Fotovvati, B., & Asadi, E. (2022). Heat treatment of Ti-6Al-4V alloy manufactured by laser-based powder-bed fusion: Process, microstructures, and mechanical properties correlations. Journal of Alloys and Compounds, 895 https://doi.org/10.1016/j.jallcom.2021.162618
