The Al?15Si?xNb coating was used as the research object to explore the effect of Nb content on the microstructure and corrosion resistance of the coating. The microstructure of the coating was observed by metallographic microscope, the phase composition of the coating was analyzed by XRD, and the corrosion behavior of the coating in 3.5% NaCl solution was characterized and discussed by electrochemical experimental methods (including open circuit potential, impedance spectrum analysis and polarization curve analysis). The results show that the Al?15Si?xNb coating is mainly composed of α?Al, primary Si and eutectic Si. A small amount of NbAl₃ phase and Nb₅Si₃ phase are formed after Nb element is added to the coating; The addition of Nb promoted heterogeneous nucleation and significantly changed the microstructure distribution of the coating. The microstructure of Al?15Si?10Nb coating has a homogeneous distribution. Uniformly distributed α?Al, primary Si and eutectic Si will form many uniformly distributed corrosion micro?battery. It can promote Al anodic reaction and make the Al₂O₃ oxide film formed on the coating surface more continuous. The polarization curve of Al?15Si?xNb coating has passivation like characteristics. When 10% Nb is used, the self?corrosion potential and pitting potential of the coating are higher, the product film resistance is larger, and the dimensional passivation current density is lower. Therefore, Al?15Si?10Nb coating has better corrosion.

Titanium alloys are widely used in the aerospace field due to their high strength, low density, corrosion resistance and other excellent properties. Therefore, it is necessary to theoretically study the evolution of titanium alloys for the quantitative design of new titanium alloys. In this paper, using the valence electron structure parameters calculated by Yu's theory, combined with the rules of cellular automata, a simulation method of the Ti?2Nb alloy β?phase solid solution microstructure was established, and he microstructures of Ti?2Nb alloys at 1 000, 1 050, 1 100, 1 150 and 1 200 ℃ were simulated. The research results show that the model method can associate the phase structure unit with the nucleation and growth of the β microstructure; the quantitative relationship between the number of nucleation points in theβmicrostructure and the solid solution temperature can be characterized by the binding energy of the phase structure unit calculated by Yu's theory; the evolution of the grain size of the β?phase microstructure with the solution time can be correlated by the simulation step. These studies can provide a reference for the establishment of a quantitative relationship between alloy composition， preparation process， structure， performance.