Influence of Annealing Temperature on the Structure and Properties of Ti3alc2 Coatings by Fcva Method

As a cermet compound, Ti3AlC2 phase has broad application prospects in aerospace and marine fields due to its excellent properties. In this paper, Ti3AlC2 coatings were prepared by a two-step method of FCVA deposition and post-annealing, and the influence of annealing temperature on the microstructure, mechanical properties and corrosion resistance of Ti3AlC2 coatings was systematically studied. The results exhibited that the phase composition and crystallinity of the coatings depended on the annealing temperature. When the temperature was 600 degrees C, the coating contained a small amount of Ti3AlC2 and TixAly with low crystallinity. As increasing the temperature to 800 degrees C, the phase in the coating was dominated by Ti3AlC2 with some TiC and Al4C3. Continuing to increase the temperature to 1000 degrees C, the phase structure of the coating gradually changed from Ti3AlC2 phase to TiC phase. In addition, the annealing temperature also had a significant effect on the mechanical and elec-trochemical properties of the coatings. As the temperature increased from 600 degrees C to 1000 degrees C, the hardness of the coating gradually increased, and the H/E value first increased and then decreased. Besides, the corrosion resistance of the Ti3AlC2 coatings increased first and then decreased with the increase of temperature, and the coating showed the best corrosion resistance when annealed at 800 degrees C.