Comparison of Domestic and Overseas Graphite/Antimony Composites and Exploration into Their Antimony-Infiltrating Technology

The technique of pressure-infiltrated antimony in porous graphite can produce sophisticated graphite seal materials. A single batch of samples of graphite/antimony matrix exhibits the differences and disparity in impregnation technology among products manufactured in the US, Japan, and China. In this study, a comprehensive analysis is conducted on the appearance, metallographic microstructure, and physical properties of these graphite/antimony composites. The results indicate that the technology of vacuum pumping before exerting high pressure has been adopted in Japan; this technique is key to removing the isopiestic layer caused by the sheer exertion of high pressure. A method has been proposed by American research where alloying is performed to raise the impregnation rate of large-scale, porous matrix by enhancing the fluidity of molten metal. However, this method cannot eliminate the air's shrinkage cavity and back-pressure and is therefore unable to achieve adequate, comprehensive performance. In China, a technological bottleneck should be investigated to improve the impregnation technology of vacuum pumping before exerting high pressure.