In situ synthesis and hardness of TiC/Ti₅Si₃ composites on Ti-5Al-2.5Sn substrates by gas tungsten arc welding

TiC/Ti₅Si₃ composites were fabricated on Ti-5Al-2.5Sn substrates by gas tungsten arc welding (GTAW). Identification of the phases was performed using X-ray diffraction (XRD). The microstructures were analyzed using scanning electron microscopy (SEM) combined with energy-dispersive X-ray spectrometry (EDS) and optical microscopy (OM). The Vickers hardness was measured with a micro-hardness tester. The TiC/Ti₅Si₃ composites were obtained in a double-layer track, and the Vickers hardness of the track increased by two to three times compared with the Ti-5Al-2.5Sn substrate.