Mechanical Properties of Cr 2 AlC Ceramics

Dense and predominantly single‐phase samples of Cr 2 AlC, together with a trace amount of Cr 7 C 3 , were fabricated by hot pressing of a mixture of chromium, aluminum, and graphite powders at 1400°C for 1 h. The hardness, Young's modulus, flexural strength, and compressive strength of Cr 2 AlC samples were 5.2, 288 GPa, 483±29, and 1159±23 MPa, respectively, which are comparable with those of Ti 3 AlC 2 and Nb 2 AlC. The material exhibits good damage tolerance. For indentation loads up to 50 N, the post‐indentation flexural strengths decrease by approximately 10% and by 31% for a load of 100 N. The flexural strengths of Cr 2 AlC samples quenched from 300°C to room temperature decrease from 483 to 455 MPa, while the retained strengths decrease quickly to 199 MPa when the quench temperature increases to 500°C. A further increase in quench temperature to 700°, 900°, and 1100°C results in a small reduction of strength.