Effect of Cr7C3 on the mechanical, thermal, and electrical properties of Cr2AlC

In this work, phase pure Cr2AlC and impure Cr2AlC with Cr7C3 have been fabricated to investigate the mechanical, thermal, and electrical properties. The thermal expansion coefficient is determined as 1.25 × 10−5 K−1 in the temperature range of 25–1200 °C. The thermal conductivity of the Cr2AlC is 15.73 W/m K when it is measured at 200 °C. With increasing temperature from 25 °C to 900 °C, the electrical conductivity of Cr2AlC decreases from 1.8 × 106 Ω−1 m−1 to 5.6 × 105 Ω−1 m−1. For the impure phase of Cr7C3, it has a strengthening and embrittlement effect on the bulk Cr2AlC. And the Cr2AlC with Cr7C3 would result in a lower high-temperature thermal expansion coefficient, thermal conductivity, specific heat capacity and electrical conductivity.

► Effect of the synthesized coexistent Cr7C3 on the mechanical properties of Cr2AlC is shown.
► Thermal and electric properties of high-purity and dense Cr2AlC are firstly determined.
► Effect of the Cr7C3 on the thermal and electric properties of Cr2AlC is firstly shown.