| Titanium silicon carbide (Ti3SiC2) is a new class of ceramic material. It combines many of the best attributes of both metals and ceramics. So it is deemed as one of the most developing perspective new ceramic materials. These unique properties enable it to future applications such as high temperature structure materials and electrode materials, etc. Ti3SiC2-SiC multiphase ceramics can release the brittleness of SiC and have good overall performance. In this work, we fabricated high purity Ti3SiC2 and Ti3SiC2-SiC composites by pressureless reactive sintering and spark plasma sintering (SPS). Based on these results we also prepared Metal/Ti3SiC2 layered materials and Metal/Ti3SiC2-SiC layered materials, and study the interface and thermal stability at elevated temperature.DSC results show that Ti3SiC2 formation peaks appeared at 1473℃, 1464℃and 1439℃respectively with the start compositions of Ti3Si1.2C2,Ti3Si1.35C2 and Ti3Si1.5C2. However there is no Ti3SiC2 formation peak was appeared up to 1500℃when the start compositions were Ti3SiC2 and Ti3Si1.1C2. All the samples can obtain high purity Ti3SiC2 bulks when sintered at 1500℃for 2 hours using pressureless sintering method. The impurities of the samples were small amount of SiC and TiSi2, only the sample with start compositions of Ti3Si1.2C2 has some Ti5Si3. We also fabricated high purity Ti3SiC2-SiC composites with the composition of Ti, Si and C are 0.42:0.23:0.35 in molar ratio, the only impurities was small amount of TiSi2. But with the start compositions of 0.8 Ti3SiC2-0.2SiC and 0.5Ti3SiC2-0.5SiC, they all have a great amount of TiC.Ti3SiC2 was prepared by SPS with the composition of Ti3Si1.2C2. The sintering time is 15 minutes and temperature is 1300℃. The sintered sample have a great amount of TiC, graphite and a small amount of Ti5Si3. However high purity Ti3SiC2 was obtained with the start composition of Ti3Si1.2C2+2 wt.%, the only impurity is a little amount of SiC phase.Samples sintered at 1300℃for 15 min using SPS method with start compositions of 0.8Ti3Si1.2C2-0.2SiC and 0.8Ti3Si1.2C2-0.2SiC+2wt.%Al, high purity Ti3SiC2-SiC composites can be obtained with a small amount of graphite as impurity, while, samples that contains no Al have some TiSi2 as impurity as well. The hardness of the sample containing Al is lower than that of the sample contains no Al, however, there is no significant difference between their densities. The three point bending strength of the samples containing Al and containing no Al are 221.0 MPa and 231.7 MPa, respectively. We also sintered 0.9Ti3Si1.2C2-0.1SiC,0.7Ti3Si1.2C2-0.3SiC,0.6Ti3Si1.2C2-0.4SiC,0.5Ti3Si1.2C2-0.5SiC and 0.2Ti3Si1.2C2-0.8SiC composites with the same sintering method.Mo/Ti3SiC2 layered composite was successfully prepared by spark plasma sintering at 1300℃K for 20 min under a pressure of 50 MPa in vacuum, with a rate of 50℃/min. After annealed for 5 h,10 h,20 h and 40 h at both 800℃and 1000℃, the Mo and Ti3SiC2 layers were metallurgically bound together with a tight and clean interface, there are no superficial defects and noticeable micro-cracks at the interface, only some micro-holes can be seen. Three intermediate layers, which are Mo2C, MoSi2 and Ti5Si3Cx, formed at the interface of the Mo/Ti3SiC2 layered composite annealed at both 800℃and 1000℃. With hold time postponing,thicknesses of intermediate layers increased but there is no other new phase formed. Thickness rised quickly at the first 10 hours of annealing then dropped dramatically and stopped in the end. Results show that the Mo/Ti3SiC2 layered composite prepared in this study has good high temperature stability.W/Ti3SiC2, W/Ti3SiC2/0.9Ti3SiC2-0.1SiC, W/Ti3SiC2/0.9 Ti3SiC2-0.1SiC/0.8Ti3SiC2-0.2 SiC, Mo/Ti3SiC2/0.9Ti3SiC2-0.1SiC, Mo/Ti3SiC2/0.9Ti3SiC2-0.1SiC/0.8Ti3SiC2-0.2SiC layered composite were produced by spark plasma sintering using Ti3SiC2 and Ti3SiC2-SiC as intermediate layers. Neat and Clean interfaces were formed without noticeable micro-cracks and micro-holes.
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