Effect of Ti5Si3 on wear properties of Ti3Si(Al)C2

Near-fully dense Ti3Si(Al)C2/Ti5Si3 composites were synthesized by in situ hot pressing/solid–liquid reaction process under a pressure of 30 MPa in a flowing Ar atmosphere at 1580 °C for 60 min. Compared to monolithic Ti3Si(Al)C2, Ti3Si(Al)C2/Ti5Si3 composites exhibit higher hardness and improved wear resistance, but a slight loss in flexural strength (about 26% lower than Ti3Si(Al)C2 matrix). In addition, Ti3Si(Al)C2/Ti5Si3 composites maintain a high fracture toughness (KIC = 5.69–6.79 MPa m1/2). The Ti3Si(Al)C2/30 vol.%Ti5Si3 composite shows the highest Vickers hardness (68% higher than that of Ti3Si(Al)C2) and best wear resistance (the wear resistance increases by 2 orders of magnitude). The improved properties are mainly ascribed to the contribution of hard Ti5Si3 particles, and the strength degradation is mainly due to the lower Young's modulus and strength of Ti5Si3.