用 于 玻 璃 热 压 印 的 高 温 快 速 均 匀 加 热 模 块 的制 造 及 优 化

Hot embossing is a promising technology for fabricating high-performance glass micro-optical components at low-cost and in a green manner. However，the efficiency and accuracy of hot embossing are limited by the long heating-cooling cycle time and the low uniformity of temperature distribution，respectively. Therefore，it is necessary to develop a high-temperature rapid uniform heating module to improve the efficiency and accuracy of hot embossing. First，a heating module based on a silicon nitride ceramic heater was designed and fabricated，and a heating test platform was constructed，enabling the real-time monitoring of the temperature distribution of the heating module. Constant-voltage heating tests were repeatedly conducted to demonstrate the reproducibility of the experiments. Subsequently，a numerical simulation model was established for the heating module，and the accuracy of the finite element model was evaluated by comparing the simulated and experimental results under the same process conditions. Numerical simulation and orthogonal tests were performed to optimize the heating module and hence obtain decent uniformity of the temperature distribution and a rapid heating rate. The experimental results indicate that the optimized heating module not only had a rapid heating rate but also a uniform temperature distribution. In the constant-voltage heating tests，the heating rate of the optimized heating module is as high as 363 ℃/min，and the maximum temperature difference is 10. 7 ℃，which validates the feasibility of the optimization method. In the controlled heating test，the measured temperature curve is essentially consistent with the set temperature curve，and the temperature fluctuation is within 0. 3 ℃. In particular，the temperature difference in the central area of 20 mm×30 mm is approximately 2 ℃ . Finally，the optimized rapid heating module and a precision temperature control system were integrated into a high-temperature hot embossing machine，which achieved efficient hot embossing of high-quality N-BK7 glass microstructure arrays.