Microstructures and mechanical, electrical, high-temperature properties of Cu/Ti2AlC FGM fabricated by hot-pressing

Abstract

The microstructure and the electrical, thermal, friction, and mechanical properties of Cu/Ti2AlC fabricated by hot-pressing at 900 °C for 1 h were investigated in the present work. Microstructural observations have shown that the plate-like Ti2AlC grains distribute irregularly in the network of Cu grains, and well-structured, crack-free bonds between the layers. With the increase in the content of Ti2AlC from layer A to layer D, the electrical resistivity increases from 1.381×10-7 Ω·m to 1.918 ×10-7 Ω·m, the hardness increases from about 980.27 MPa to about 2196.01 MPa, and the friction coefficient from above 0.20 reduces to about 0.15. Oxidation rate increases with the increases of temperature. Exfoliation was obviously observed on the surface of oxidation layer A. The surface of layer D was still intact and the spalling and other defects were not found. The mass decreases in the acid solution, and increases in the alkaline solution. The largest corrosion rate is found in 6.5% HNO3 or 4% NaOH solution.