Papers by Author: Xin Hua Chen

Abstract: A series of new sub-micro-layered Ti3C2/(Cu-Al) cermets were prepared by in-situ hot-extruding a mixture of Ti3AlC2 and Cu powders, and some properties of these materials were tested. These cermets have quite high fracture strength and electric conductivity, due to the strong combination between Ti3C2 and (Cu-Al), and a special network microstructure formed by the (Cu-Al) phase surrounding the sub-micro-sheet layered Ti3C2 phase. The in-situ hot-extruding after pressless sintering can effectively eliminate pores contained in (Cu-Al) phase, and accelerate the diffusing of Cu towards the interlayer between Ti3C2 layers, so the fracture strength and electric conductivity are increased. With increasing the content of the ceramic phase, the strength of the cermets can be further increased while the ductility is reduced.

Abstract: Highly pure and dense bulk Ti2AlC was prepared by hot-pressing a mixture of the “312” phase Ti3AlC2 powders, and the element Ti and Al powders. Different ratios of the starting materials and different sintering temperature were attempted in order to obtain a highly pure and dense bulk Ti2AlC sample. Phase analysis and microstructures observing were performed by using by XRD, SEM as well as an X-ray fluorescence spectrometer. The results show that a nearly full dense bulk Ti2AlC sample can be prepared at 1300°C and 30MPa for 30 minutes in argon atmosphere. A dominant mechanism to form the “211” phase Ti2AlC can be attributed to the directly connecting between Al and Ti6C octahedron, which is as an intermediate phase in the Al-rich liquid mediator during the hot pressing.