Papers by Author: Jing Zhai

Abstract: _{Subscript text} Nd can obviously improve the mechanical properties of spray deposited 1%Nd, 2%Nd extruded and heat treatment alloy. Nd solid solution in α-Mg matrix lead to the hardness of 2%Nd spray deposited magnesium alloy extruded is higher than that of after heat treatment. A large number of Al₂Nd particles precipitation is the key factor to the highest hardness value(139.4Hv) in 2%Nd magnesium alloy after 370°C/3h+205°C/24h heat treatment. Moreover, the precipitation of Al₂Nd accompany with Al₂Ca and Al-Mn phase increased.

Abstract: A kind of slurry which is applicable for fine atomizing CMP was made and the optimal results were obtained through orthogonal experiments by comparing fine atomizing CMP and traditional CMP. The research results show that the material removal rate of fine atomizing CMP is 52.23% of traditional CMP, and the dosage of the slurry used in fine atomizing CMP only accounts for 10 vol% compared to traditional CMP. The surface roughness after the fine atomizing CMP is 2.5nm which is better than that of the traditional CMP (3.0nm).

Abstract: In the chemical mechanical polishing process, the relationship of relative motion of polishing pad and polishing head plays very important role for CMP quality. This paper established the mathematical model in order to investigate the relative motion of polishing pad and polishing head. It was found that the speed ratio of polishing pad and polishing head shows great influence on the CMP uniformity. And when the value of speed ratio of relative rotation approaches 1.23, the distribution of abrasives’ trajectories is close and uniform. Theoretically, the surface quality of workpiece is better.