The Ta coating with corrosion resistance is grown on the γ-TiAl substrate by double-glow plasma surface metallurgy technique, followed by the electrochemical test in 10 wt%, 20 wt% HCl and 10 wt%, 40 wt% H 2 SO 4 solution. The data of nanohardness and elastic modulus are collected by the nanoindention test. The adhesion strength of Ta coating is investigated by means of the scratch test. The study of corrosion resistance is performed using potentiodynamic polarization and electrochemical impedance spectroscopy and measured by SEM and X-ray diffraction. Results highlight that the Ta coating is tightly bonded to the γ-TiAl substrate, consisting of the deposition layer and diffusion layer. Experimental data indicate that the Ta coating presents excellent corrosion resistance, which is confirmed by the high values of polarization resistance (R p ) and the low values of corrosion current density (i corr ). The surface nanohardness of the Ta coating is improved from 3.41 to 7.29 GPa, nearly twice of that of the substrate. The Ta 2 O 5 formed on the coating is able to hold back the penetration of adverse ions inwardly, owing to its dense structure and adhesion effect.

A Lean Premixed Prevaporised (LPP) low-emission combustor with a staged lean combustion technology was developed. In order to study cold-flow dynamics in the LPP combustor, both experimental tests using the particle image velocimetry (PIV) to quantify the flow dynamics and numerical simulation using the commercial software (FLUENT) were conducted, respectively. Numerical results were in good agreement with the experimental data. It is shown from the observation of the results that: there is a Primary Recirculation Zone (PRZ), a Corner Recirculation Zone (CRZ) and a Lip Recirculation Zone (LRZ) in the LPP combustor, and the exchanges of mass, momentum and energy between pilot swirling flow and primary swirling flow are contributed by the velocity gradients, and the shear flow is transformed into a mixing layer exhibiting the higher Reynolds stresses, which suggests the mixing process is strictly affected by the Reynolds stresses.