A novel TiAl 3 -Al coating was prepared by cold spray for high temperature protection of titanium aluminum-based alloy. The substrate alloy was orthorhombic-Ti-22Al-26Nb (at.%). The composite coating was mainly composed of TiAl 3 embedded in the matrix of residual aluminum. An interlayer about 10 lm was formed between the coating and the substrate. The oxidation test indicated that this composite coating was very effective in improving the high-temperature oxidation resistance of the substrate alloy at 950°C in the tested 150 cycles without any sign of degradation. The microstructure analysis of the oxidized composite coating showed that an Al 2 O 3 scale with a complex structure can be formed outside the interlayer during oxidation and no oxides beneath the interlayer were detected, which indicated that the complex continuous Al 2 O 3 and the interlayer provide the protection of the substrate at high-temperature oxidation condition.

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(Sr0.97Eu0.01Dy0.02)Al2O4 persistent luminescence (PersL) ceramics were fabricated by solid‐state reactive sintering in vacuum combined with hot isostatic pressing (HIP) using H3BO3 as a sintering additive. The phase composition, microstructure, luminescence properties, trap state, and PersL performance of HIP post‐treated (Sr0.97Eu0.01Dy0.02)Al2O4 PersL ceramics were discussed. For the (Sr0.97Eu0.01Dy0.02)Al2O4 PersL ceramics after HIP post‐treatment, the initial luminescence intensity of the ceramics reached over 6400 mcd/m2 with simulated daylight irradiation of 1000 lx for 5 min, and the persistent emission decay time > 17 h. This is much better than the SrAl2O4:Eu2+,Dy3+ PersL powders and the other luminescent ceramics. In addition, this method is a solid‐state reactive sintering method for synthesizing ceramics, which has the advantages of low cost and simple operation, and is suitable for large‐scale, high‐volume industrial production.