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KDP crystal is difficult to fabricate for high precision. because it is brittle soft and with high heat expansion. Magnetorheological finishing (MRF) has been used to machine KDP for high precision. However, iron powders are easily embedded into KDP surface. Ion beam figuring (IBF) can clean iron powders embedded and enhanced laser-induced damage resistance. However, the thermal effect introduced by incident ions is a headachy problem. Temperature fields have been calculated by finite element simulation and measured by experiments. Thereof temperature fields of optical component bombarded by low energy ion beam were estimated and this estimate method is proved to be correct and feasible by comparing results of finite element simulation and experiments. And then, thermal stress of KDP under ion beam irradiation was calculated and discussed. Distributions of temperature and stress on KDP surface are accordant with beam current distribution. Temperature and stress rise quickly under ion beam irradiation, while decreases rapidly without ion beam irradiation. Peaks of temperature and thermal stress tend to periodicity. The period corresponds the period of ion beam moving spasmodically and fleetly in Y direction. Tensile stresses are not visible at X/Y/Z direction, but compressive stress at X direction is larger obviously than that of Y/Z direction.

Ion beam figuring (IBF) is an advanced machining technology for high precise optical component. For brittle materials with high thermal expansion coefficient such as KDP crystal, thermal effect is an intractable problem due to the accumulative heat introduced by incident ions on optical surface. Asymmetrical heating induces rapid changes of thermal stress and once the thermal stress exceeds the mechanical strength, the component may crack or break. In this paper, the number of scanning rows was factorized to various combinations with times of scanning and the number of moving rows. Temperature field and thermal stress of each combination were simulated using finite element analysis software ANSYS. Comparing with the results, the much better combination was found. With optimized scanning path, peak of thermal stress is lower than that of traditional scanning path. Especially, peak of tensile stress on X-distance and Y-distance were reduced obviously. At last, a law for optimization was established: when times of scanning and the number of scanning rows are equal or approximately equal, the thermal stress appears lower.

With the gradual depletion of fossil fuels and the increasingly severe form of environmental protection, data analysis shows that the new energy vehicle industry has become the future industry competing for development all over the world. China has also established the development strategy and goal of the new energy vehicle in the future. This paper analyzes the technical route and application data of new energy vehicle and puts forward the development strategy of new energy vehicle industry in view of the current situation and existing problems of the development of new energy vehicle in China. It is necessary to strengthen the formulation of national standards for energy vehicle industry, pay attention to core technology breakthroughs and parts research, improve infrastructure construction, constantly improve the business promotion mode, so as to promote the rapid development of new energy vehicle industry in China.