A Finite Element Analysis for Improvement of Shaping Process of Complex-Shaped Large-Size Silicon Carbide Mirrors

Materials

Ge Zhang¹  Congcong Cui¹  Yingnan Wan²  Jingchuan Zhu²  Ling Qiao² 

[1] Key Laboratory of Optical System Advanced Manufacturing Technology, Chinese Academy of Sciences, Changchun 130033, China;School of Material Science and Engineering, Harbin Institute of Technology, Harbin 150001, China;

关键词: finite element analysis;    gel-casting process;    silicon carbide;    defects;    loading speed;    exhaust hole;   

DOI  :  10.3390/ma14154136

来源: DOAJ

【 摘 要 】

In the gel-casting process, the proper selection of technological parameters is crucial for the final quality of a green body. In this work, the finite element method is used to investigate the mold characteristics in the gel-casting process, and the typical flow behaviors under different conditions are presented. Based on the distribution characteristics of temperature, pressure and flow field of gel polymer, the simulated results provide some possible reasons for the generation mechanisms of defects. Then, a series of simulations were performed to investigate the effect of process parameters on the molding quality of green gel-cast bodies. The results show that the decreasing loading speed can effectively reduce the number of defects and improve the molding quality. In addition, this paper presents a new technique by applying the exhaust hole to decrease the number of defects and, hence, improve structural integrity. The influence of the loading speed on the mold characteristics is well understood for the gating system with an exhaust hole, which suggests to us appropriate parameters for optimizing the molding design. This work provides a theoretical basis to explicate the generating mechanism of defects involved in the gel-casting process and acquires an optimized technique to produce a silicon carbide green body.

【 授权许可】

Unknown