Effect of heat treatment on the microstructure and properties of CoCrFeNiMo0.2 particles reinforced titanium matrix composites

In this paper, the influence of heat treatment process on the microstructure and properties of CoCrFeNiMo0.2/Ti composites was studied by heat treatment of the composites. The structure and composition of CoCrFeNiMo0.2/Ti composites were characterized by X-ray diffraction and optical microscope. The distribution of elements of the interface layer was explored by electron probe. The mechanical properties of the composites were analyzed by nano indentation experiment and hardness tester. The relationship between irregular particles and the thickness of the interface layer was studied. The results are as follows: when the heat treatment temperature is 770 °C, the morphology of the high entropy alloy does not change significantly. As the temperature rises to 830 °C, the shape of the particles deforms and the thickness of the diffusion layer increases significantly. With the increase of the heat treatment temperature, the Young’s modulus and hardness of the interface layer have increased. When the heat treatment temperature rises to 890 °C, the particles completely diffuse into the matrix. Overall, the distance of the particles from the inscribed circle and the thickness of the interface layer are positively correlated. •High entropy alloy reinforced titanium matrix composites were prepared.•With increasing temperature and time, the morphology of particles becomes irregular and the interface layer becomes thicker.•With the increase of the heat treatment temperature, the Young's modulus and hardness of the interface layer have increased.•The distance of the particles from the inscribed circle and the thickness of the interface layer are positively correlated.