Investigation of Post-weld Heat Treatment of Laser Welded Ti6Al4V Materials

Abstract

In this study, the changes in the internal structure and mechanical properties of laser-welded Ti6Al4V material after heat treatment were experimentally investigated. The transformation temperatures of the α and β phase structures of the Ti6Al4V material influenced the heat treatment temperatures. Optical microscopes, XRD, and SEM experiments were performed to detect the microstructural change. Hardness and tensile tests were also carried out to determine the change in mechanical properties. The experimental study determined that the mechanical properties of laser-welded Ti6Al4V material improved after heat treatment. It was observed that ductility and strength increased significantly at heat treatment temperatures above the β phase temperature. It was determined that the Widmanstatten morphology visible in the weld area increased the hardness.

Keywords

• Laser welding
• Ti6Al4V
• Heat treatment

Supporting Institution

Manisa Celal Bayar Üniversitesi BAP Birimi

Project Number

2020-047

Thanks

The authors thank Manisa Celal Bayar University for financial support (BAP project number 2020/47).

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