Multiscale Simulation Of Ni-Cr Sheet Deposited By EB-PVD

In order to meet the requirement of the fourth generation metal thermal protect system development, it is necessary to prepare large scale high-temperature alloy sheet. It is a good way to prepare large scale high-temperature alloy sheet by electron beam physical vapor deposition (EB-PVD) technology. However, the EB-PVD equipment is voluminous, and its craft is complex, experiment is inefficiency and costly. Therefore, it is necessary to search for other method except for experiment to systematically approach the relationship of material performance and process parameters. Nowadays, the developments of computer and theory physics have present necessary conditions for EB-PVD sheet deposition simulation. In the dissertation, two-dimension kinetic Monte Carlo (KMC) method and cellular automata (CA) method have been integrated to simulate investigate material microstructure for a range of process parameters, namely, substrate temperature, deposition rate and incident angle. In the last part, the performances of large scale alloy sheet along substrate radial have been explored at substrate temperature of 500K(2D temperature) and the maximum theory deposition rate of 2.5μm/min.In the KMC simulation, embedded atom method (EAM) was adopted to represent the atomic interaction of Nickel, and the EAM alloy model was used to describe the interaction between Nickel and Chrome atom. The initial configuration of adatom was located through Momentum Scheme, and diffusion activation energies of all diffusion configurations was calculated by molecular statics (MS) calculation, at last, red and black tree search was used to update jump rates for every path. Surface roughness factor and packing density were applied to evaluate the simulation results, and fractal theory was used to study the thin film fractal for different substrate temperature and different deposition rate. In order to approach sheet performance, effects of thermal holding time on thin film microstructure were approached by KMC simulation, and cellular evolution rules were established based on all the KMC simulation. In order to examine and certify simulation results, large scale alloy sheet was prepared using the corresponding process parameters with CA simulation, and atom force...