Hu Shunchang, Sun Peiyan, Zhang Zhen, Zhang Guojun, Ming Wuyi
Henan Key Laboratory of Intelligent Manufacturing of Mechanical Equipment, Zhengzhou University of Light Industry, Zhengzhou 450002, China.
Guangdong Provincial Key Laboratory of Digital Manufacturing Equipment, Guangdong HUST Industrial Technology Research Institute, Dongguan 523808, China.
Micromachines (Basel). 2024 Oct 17;15(10):1264. doi: 10.3390/mi15101264.
The heating system is an essential component of the glass molding process. It is responsible for heating the glass to an appropriate temperature, allowing it to soften and be easily molded. However, the energy consumption of the heating system becomes particularly significant in large-scale production. This study utilized G-11 glass for the simulation analysis and developed a finite element model for the thermal conduction of a 3D ultra-thin glass molding system, as well as a thermal bending model for smartwatches. Using finite element software, the heat transfer between the mold and the glass was modeled, and the temperature distribution and thermal stress under various processing conditions were predicted. The findings of the simulation, when subjected to a numerical analysis, showed that heating rate techniques significantly affect energy consumption. This study devised a total of four heating strategies. Upon comparison, optimizing with heating strategy 4, which applies an initial heating rate of 35 mJ/(mm·s) during the initial phase (0 to 60 s) and subsequently escalates to 45 mJ/(mm·s) during the second phase (60 to 160 s), resulted in a reduction of 4.396% in the system's thermal output and a notable decrease of 7.875% in the heating duration, respectively. Furthermore, a single-factor research method was employed to study the forming process parameters. By comparing the numerical simulation results, it was found that within the temperature range of 615-625 °C, a molding pressure of 25-35 MPa, a heating rate of 1.5-2.5 °C/s, a cooling rate of 0.5-1 °C/s, and a pulse pressure of 45-55 Hz, the influence on residual stress and shape deviation in the glass was minimal. The relative error range was within the 20% acceptable limit, according to the experimental validation, which offered crucial direction and ideas for process development.
加热系统是玻璃成型工艺的一个重要组成部分。它负责将玻璃加热到合适的温度，使其软化并易于成型。然而，在大规模生产中，加热系统的能源消耗变得尤为显著。本研究使用G-11玻璃进行模拟分析，开发了一个用于3D超薄玻璃成型系统热传导的有限元模型以及一个用于智能手表的热弯曲模型。利用有限元软件，对模具与玻璃之间的热传递进行了建模，并预测了各种加工条件下的温度分布和热应力。模拟结果经过数值分析表明，加热速率技术对能源消耗有显著影响。本研究总共设计了四种加热策略。经比较，采用加热策略4进行优化，即在初始阶段（0至60秒）施加35 mJ/(mm·s)的初始加热速率，随后在第二阶段（60至160秒）升至45 mJ/(mm·s)，分别使系统的热输出降低了4.396%，加热持续时间显著减少了7.875%。此外，采用单因素研究方法对成型工艺参数进行研究。通过比较数值模拟结果发现，在615 - 625°C的温度范围内、25 - 35 MPa的成型压力、1.5 - 2.5°C/s的加热速率、0.5 - 1°C/s的冷却速率以及45 - 55 Hz的脉冲压力下，对玻璃中残余应力和形状偏差的影响最小。根据实验验证结果，相对误差范围在20%的可接受极限内，这为工艺开发提供了关键的方向和思路。
