Effect of Si Content on the Synthesis of Ti_3SiC_2 Bulk Material by Pressureless Sintering

摘要

Ti_3SiC_2 is a bioinert material. The combination of high fracture toughness, excellent corrosion resistance and easy machinability make it a new class of potential biomaterials for orthopedic applications, dental implants, and fixation devices for the bone. In this paper, effect of Si concentration on the sintering of Ti_3SiC_2 bulk material was reported. Ti_3SiC_2 bulks were fabricated by pressureless reactive sintering of powder compacts made of Ti, Si and graphite powders. Nearly pure Ti_3SiC_2 bulk was obtained by reactive sintering of the powder compact, with a nominal composition of 3:1.1:2 in molar ratio of Ti:Si:C, at 1500 °C for 120 minutes. TiC, a non-preferable impurity was avoided by the appropriate addition of excess Si (relative to stoichiometric composition of 3:1:2 in Ti_3SiC_2). However, too much Si will result in the formation of significant amount of TiSi_2 and SiC in the sintered Ti_3SiC_2- Microstructure of the prepared Ti_3SiC_2 bulks was analyzed by scanning electron microscope. Phase constituent analysis was carried out by x-ray diffraction. Effect of Si content on the density of sintered samples was also studied.