Comparison of Layerwise Preheating and Post-heating Laser Scan on The Microstructure and Mechanical Properties of L-PBF Ti6Al4V

This study aimed to investigate the evolution of the microstructure and mechanical properties of asfabricated laser powder bed fusion (L-PBF) Ti-6Al-4V samples by introducing layerwise pre-heating or post-heating laser scans. Multiple laser scans, varying in scanning speed at constant power, were examined before the melting laser scan (pre-heating) or after it (post-heating). The analysis focused on microstructural features such as porosity, and α-phases lath structure, as well as the hardness response of the material. The results revealed the additional layerwise scans had a significant impact on reducing porosity by up to 98% when the additional scan was applied prior to or upon the melting scan. Additional laser scans decreased the microstructure and mechanical response variation along different orientations. Furthermore, these findings highlight the potential of layerwise heating strategies to improve the overall quality and performance of L-PBF Ti-6Al-4V components, thus paving the way for enhanced applications in various industries such as aerospace.