Multi-objective optimization of hot embossing process for high-quality glass micro gratings

• Published in: Sensors and actuators. A. Physical. Vol. 374; p. 115482
• Main Authors: Yang, Gao, Li, Jianzhi, Liu, Jiashun, Gong, Feng
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 16.08.2024
• Subjects: Glass hot embossing; Glass micro grating; Multi-objective optimization; Replication accuracy; Replication accuracy; Multi-objective optimization; Glass micro grating; Glass hot embossing
• ISSN: 0924-4247; 1873-3069
• DOI: 10.1016/j.sna.2024.115482

This study proposed a multi-objective optimization strategy to produce high-quality glass micro gratings. The applied methods include factor screening, surface response methodology (RSM), non-dominated sorting genetic algorithm (NSGA-II) and decision-making. Specifically, the significant factors were selected among several process parameters in hot embossing through screening experiments. Afterward, the regression models for the transferred ratio, uniformity of glass microstructures and warpage concerning those significant process parameters were established. Meanwhile, the significance of selected factors and their interactions was analyzed. Based on the regression models, the Pareto front was obtained by using NSGA-II program, where the top 10 solutions were applied in glass hot embossing. Finally, a decision-making strategy was employed to further choose a feasible solution that allows the fabrication of glass micro gratings with a high transfer ratio, high uniformity, low warpage, low surface roughness, and no defect. The experimental results indicated that embossing temperature has the most significant effect on the replication accuracy of glass micro gratings, followed by embossing force and embossing time. However, warpage was not significantly sensitive to any process parameters in this hot embossing process. The defect-free glass micro gratings could be eventually fabricated under the optimal process parameters, achieving a transfer ratio and uniformity of higher than 95 % and 83 %, respectively. Moreover, their Ra surface roughness and warpage can be lower than 13 nm and 1.5 μm. The satisfactory quality of embossed micro gratings revealed that the proposed multi-objective optimization strategy is feasible in glass hot embossing. [Display omitted] •A multi-objective optimization strategy was proposed for glass hot embossing process.•The effects of process parameters on transferred ratios, uniformity and warpage were experimentally investigated.•The defect-free glass micro gratings with satisfactory replication accuracy were successfully fabricated.