Heat-treatment effect on anti-corrosion behaviour and tribological properties of LENS in-situ synthesized titanium aluminide

Abstract

Development of titanium aluminide (Ti–Al) based alloys has generated a huge interest for many high temperature industrial applications due to their extensive properties. Ti–Al has useful properties in terms of high temperature stability and enhanced strength. Additive Manufacturing (AM) using Laser Engineered Net Shaping (LENS) is breaking the edges of advance manufacturing procedure with the possibility of changing the perception of alloy development, design and structural manufacturing in totality. This study aims to investigate the effect of annealing heat-treatment (HT) at 1200 °C on the binary Ti–Al. The morphological evolution and the phases formed post manufacturing and HT were examined using scanning electron microscopy (SEM) coupled with energy dispersive spectrometry (EDS) and X-ray diffractometry (XRD), respectively. The micro-hardness and corrosion properties of the alloy were studied using a diamond base micro hardness tester and potentiodynamic polarization method, respectively. In-situ fabricated TiAl alloy displayed good mechanical properties and corrosion resistance properties before and after HT.

Keywords

• LENS
• In-situ manufacturing
• Microstructure
• Microhardness
• Corrosion
• Tribology