标题：In-situ synthesis of SiC particles by the structural evolution of TiCxin Al-Si melt
作者：Nie, Jinfeng ;Li, Dakui ;Wang, Enzhao ;Liu, Xiangfa
作者机构：[Nie, Jinfeng ] Nano Structural Materials Center, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 2 更多
来源：Journal of Alloys and Compounds
摘要：A facile method has been developed to in-situ synthesize SiC particles utilizing the structural instability and evolution of TiCxin Al-Si melt. It is considered that the synthesis of SiC particles occurs via the gradual reaction between TiCxand Si atoms, whilst Si content plays the crucial role in this approach. If the Si content in the melt is above 30%, TiCxdirectly reacts with Si and Al to form SiC, but the needle-like TiAlxSiyphase formed simultaneously will do harm to the mechanical properties of the composites. Thus, it is proposed to add B element in the melt to transform the TiAlxSiyinto TiB2particles. Therefore, the SiC and (SiC + TiB2) hybrid-particles reinforced Al-18Si composites were successfully prepared using the method. In the composites, the SiC particles have the size range from 2.5 to 7.5 μm and a block-like morphology. Furthermore, the mechanical properties of base alloy, including the wear resistance and macro-hardness, have been obviously improved by the in-situ SiC particles. Besides, the relevant underlying mechanisms are also discussed. © 2014 Elsevier B.V. All rights reserved.