Eutectic composition titanium metal matrix composites for laser powder bed fusion via surface remelt analyses

Abstract

Ti-based metal matrix composites (MMCs) represent a material class with highly desired performance for the aerospace industry, but implementation has been hindered by poor processability. It is now being realised that MMCs can be formed in situ through the exploitation of rapid cooling rates of laser powder bed fusion, and targeting invariant reaction compositions to minimise the propensity for solidification cracking. We perform laser line scans and surface remelts of arc-melted Ti–0.38C, Ti–1.67B, Ti–8.5Si and Ti–32.5Fe wt-% eutectic compositions to assess potential material amenability to the laser powder bed fusion (LPBF) process at low cost as well as determining the nanostructure and hardness properties. The results indicate that MMCs are amenable to LPBF and may outperform conventional alloys.