Modeling of effective design of high pressure anvils used for large scale commercial production of gem quality large single crystal diamond

• Published in: Diamond and related materials 2011-07, Vol.20 (7), p.969-973
• Main Authors: Han, Qi-Gang, Li, Ming-Zhe, Jia, Xiao-Peng, Ma, Hong-An, Li, Yuefen
• Format: Article
• Language: English
• Subjects: Anvil; Anvils; Bevels; Cross-disciplinary physics: materials science; rheology; Cubic high-pressure apparatus; Design engineering; Exact sciences and technology; FEM; Finite element method; Fullerenes and related materials; diamonds, graphite; Large single crystal diamond; Materials science; Mathematical analysis; Mathematical models; Optimization; Physics; Single crystals; Specific materials
• ISSN: 0925-9635; 1879-0062
• DOI: 10.1016/j.diamond.2011.05.017

In order to overcome disadvantages of the substantial cost associated with the tungsten carbide (WC) anvil used for large scale commercial production of gem quality large single crystal diamonds, we have developed a modeling of effective design of WC anvil by finite element method (FEM). Our results indicate that the bevel length ( l) and the bevel angle (α) of anvil have a significant effect on the performance of large volume cubic high pressure apparatus (LV-CHPA). Firstly, to gain the same cell pressure, the system oil pressure is decreases as l decreases or α increases. Secondly, the probability of failure crack in the anvil is increases as l decrease to 12 mm or α increase to 43°. Thirdly, the optimum value of l and α should be 13 mm and 41.5°, which can increase the performance of LV-CHPA farthest. The results have been proved by technical production. This would greatly help to improve the cubic anvil type high pressure techniques. ► The system oil pressure decreases as l decreases or α increases. ► The failure crack increases as l decrease to 12 mm or α increase to 43 degree. ► The optimum value of l and α should be 13 mm and 41.5 degree.