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Ti/Al/TiC mixed powders were used as the raw materials for the fabrication of functionally graded material (FGM) by hot pressing sintering. The sample was analyzed by SEM combined with Metallographic microscope and Energy Disperse Spectroscopy,The results show that each layer is composed of TiC and Ti2AlC, without containing other phases. The size of TiC grains are about 3-6 μm. With TiC content in the layers increasing, Ti2AlC grains gradually decrease. The lathy Ti2AlC grains of the FGM have a length of about 10 μm and a width of about 4 μm. The interface of each layer has a good combination with a certain thickness transition layer.Microhardness tester is used to analyse the hardness of material.The results show that the Vickers hardness of every layer increases with TiC content increasing. The thermal shock performance test found that material has good thermal shock performance.

Europium-doped nanocrystalline ZrO2: Eu3+ powders with different doped concentrations were prepared by emulsion processing method, with different doped concentration and calcination temperature on the material grain size, structure, size and luminescent properties. The results show that: Eu3+ has a stabilizing effect on tetragonal phase of ZrO2. Emission spectra indicates that the main emission peak in the 593m and 608m, “Blue Shift “will occur in 5D0 → 7F2 transition of the emission spectra of sample with the sintering temperature at 1000℃. Samples with the sintering temperature soaring, spectral emission intensity also increases.

The cyclic oxidation behavior of Ti2AlN and Ti2AlN/TiN composites were investigated at 800℃, 900℃ and 1000℃. The phase composition, thickness of oxidation layer and element content of samples were investigated by XRD and SEM coupled with EDS. The cyclic oxidation behaviors generally follow a parabolic rate law, with good thermal shock resistance. The antioxidation property of Ti2AlN/TiN composite is better than Ti2AlN. Oxidation process of single-phase Ti2AlN is composed by the outward diffusion of Al3+ and Ti4+, and inward diffusion of oxygen. Oxidation process of Ti2AlN/TiN composite consists of two parts: firstly, the oxidation of TiN, the oxidation temperature is 500℃; the second step is the oxidation of Ti2AlN, carried out in the 800-1000 ℃.

The isothermal oxidation behaviors at 800-1000℃ for 20h in air of bulk Ti2AlN and Ti2AlN/TiN were investigated by TG, XRD and SEM coupled with EDS. The oxidation behaviors generally follow the parabolic law. The activation energies of Ti2AlN and Ti2AlN/TiN composite are 614.93 KJ∙mol-1 and 541.35 KJ∙mol-1 respectively. The antioxidation property of Ti2AlN/TiN composite is better than Ti2AlN. Oxidation process of single-phase Ti2AlN is composed by the outward diffusion of Al3+ and Ti4+, and inward diffusion of oxygen. Oxidation process of Ti2AlN/TiN composite consists of two parts: firstly, the oxidation of TiN, the oxidation temperature is 500 ℃; the second step is the oxidation of Ti2AlN, carried out mainly in the 800-1000 ℃.