The in-situ synthesis of TiC in Cu melts based on Ti-C-Si system and its mechanism

Introduction of carbon into metal melts, especially those with limited carbon solubility, for composites preparation by casting method is very difficult due to the poor wettability between carbon and melts. In this work, carbon in various forms has been effectively introduced into Cu melts and TiC has been in-situ synthesized based on Ti-C-Si system, and its mechanism has been investigated. It is found that, after the addition of Ti-C mixture into Cu melts, carbon can be wetted by Cu through Ti-C reaction. However, because of the TiC interconnected network formation, the mixture tends to become the block which cannot be dispersed into the melts. Using Ti-C-Si instead of Ti-C system is an effective way to wet carbon and in-situ synthesize TiC while prevent the formation of TiC network. It is considered that Si changes the reaction pathway of the system. The Ti5Si3 which is prior to be formed in Ti-C-Si system can prevent the following formed TiC from interconnecting and its subsequently dissolution due to TiC formation can further help the products to distribute more uniformly in Cu melts. (C) 2019 The Authors. Published by Elsevier Ltd.