【作者】 刘玉成；

【导师】 杨延清；

【作者基本信息】 西北工业大学 ， 材料学， 2007， 硕士

【摘要】 钛基复合材料（TMC）将钛合金的塑性与增强体SiC纤维的优越承载能力相结合，表现出良好的性能；使其即使在600～800℃的高温下，仍具有卓越的强度、韧度、刚度和蠕变抗力。TMC因其高的比强度和比模量以及极佳的疲劳和蠕变性能，优异的高温性能及耐蚀性能而倍受瞩目，在航空航天工业中有着广泛的应用前景。 该实验以国产SiC纤维为增强体，制备SiC／Ti600复合材料，作为对比，还制备了SiC／Ti-6Al-4V复合材料。结果表明，采用40W／1h的反溅射工艺，800W／2.0Pa／2.0h+800W／3.0Pa／8.0h的溅射工艺使得涂层和纤维结合较好，得到厚度均匀的钛合金涂层，具有纳米晶粒。并且该工艺的沉积速率也满足实验要求。 利用SEM、EDS以及XRD等分析手段，比较研究了SiC／Ti600、SiC／Ti-6Al-4V和SiC／C／Ti-6Al-4V复合材料的界面反应产物。探讨了SiC／Ti600复合材料拉伸强度低的原因。研究表明，SiC／Ti600和SiC／Ti-6Al-4V的界面反应产物基本一样，为TiC、Ti₅Si₃、Ti₃SiC₂等；由于SiC／C／Ti-6Al-4V的SiC纤维含有碳涂层，界面反应产物仅为TiC。根据界面反应产物的生长动力学计算得到了SiC／Ti600、SiC／Ti-6Al-4V和SiC／Ti-6Al-4V三种复合材料的反应动力学参数K₀和^k。表明SiC／Ti600复合材料相对于SiC／Ti-6Al-4V和SiC／C／Ti-6Al-4V复合材料有更好的界面稳定性。但是实验制备出的SiC／Ti600复合材料纵向拉伸强度很低。国产SiC纤维性能差是其主要原因，基体脆性和裂纹以及制备过程中纤维的损伤也是拉伸强度不高的原因。 研究结果对进一步研究SiC／Ti复合材料有一定的借鉴作用。更多还原

【Abstract】 The continuous silicon carbide fiber （SiC） reinforced titanium matrix composites （TMC） make full use of constitutive properties such as higher strength and toughness of silicon carbide fiber, plasticity and mold ability of titanium matrix. These all make it keep better fatigue and creep resistance at elevated temperature up to 600～800℃. TMC has attracted considerable interest as materials for components in elevated temperature aerospace and gas turbine applications because of higher specific tenacity and modulus, outstanding fatigue and creep properties, wonderful elevated temperature property and erosion resistance.The way of matrix-coated fiber was used to manufacture the composite of Ti600 reinforced with the domestic SiC fiber. For comparison, the SiC/Ti-6Al-4V was also prepared. Under the conditions of 40w/lh for cleaning the fiber and 800W/2.0Pa/ 2.0h+800W/3.0Pa/8.0h for sputtering the matrix alloy with faster deposit rate, the nano grained Ti600 and Ti-6Al-4V alloys were deposited onto the SiC fiber with exellent bonding between fiber and coating, homogeneous thickness and chamical composition.The interfacial reaction of the composites was investigated by means of scanning electron microscope （SEM）, X-ray diffraction （XRD） and energy dispersive X-ray spectrometer （EDS） and the effect on the tensile property was discussed. The interfacial reaction products of SiC/Ti600, SiC/Ti-6Al-4V and SiC/C/Ti-6Al-4V were compared. The interfacial reaction products of SiC/Ti600 are basically the same as those of SiC/Ti-6Al-4V, mainly TiC, Ti₅Si₃ and Ti₃SiC₂. But only TiC was found as interfacial reaction product of the SiC/C/Ti-6Al-4V composite because of the C coating on the outmost surface of the SiC fiber. The kinetic values of K₀ and Q^k for the growth of the interfacial reaction zone in the SiC/Ti600, SiC/Ti-6Al-4V and SiC/C/Ti-6Al-4V composites were obtained and compared. It is shown that the interface of SiC/Ti600 is more stable than that of the other two kinds of composites. However, the longitudinal tensile strength of SiC/Ti600 is very poor due to the poor更多还原