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B4C(W,Ti)C陶瓷复合材料的制备及其性能 总被引:11,自引:0,他引:11
采用热压烧结工艺制备了B4C/(W,Ti)C陶瓷复合材料.研究表明:B4C/(W,Ti)C陶瓷材料烧结时将产生化学反应,反应产物为TiB2和W2B5.B4C/(W,Ti)C陶瓷材料的性能与(W,Ti)C的含量密切相关,随(W,Ti)C含量的增加,材料的致密度、抗弯强度和断裂韧性逐渐增加,硬度逐渐减小;当保温时间低于50min时,材料的致密度、抗弯强度和硬度显著降低;B4C/(W,Ti)C陶瓷复合材料的最佳性能参数为:抗弯强度693MPa,维氏硬度23.5GPa,断裂韧性3.9MPa·m1/2.磨损实验表明,B4C/(W,Ti)C陶瓷材料在低速小载荷的实验条件下,耐磨性能优异,在高速大载荷的实验条件下,磨损过程中局部点的高温导致试样表面发生氧化,加剧了材料的磨损. 相似文献
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以板状刚玉为骨料,两种原料体系:TiC/Ti/Si,TiC/Ti/SiC作基质相,酚醛树脂作结合剂,在氩气保护下于1350~ 1550℃制备Ti3SiC2结合刚玉材料.研究了原料体系和烧成温度对其相组成、显微结构及常温物理性能的影响.结果表明:两种原料体系制备所得Ti3SiC2结合刚玉材料的相组成均为Al2O3,Ti3SiC2和TiC.两种原料体系在1350-1400℃合成材料耐压强度较高;随着烧成温度升高,其耐压强度减小.其中,Ti3SiC2结合刚玉材料采用体系TiC/Ti/Si,在1400℃烧结6h获得最佳综合性能:基质相中Ti3SiC2含量达到64%,耐压强度为65 MPa. 相似文献
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Ti3SiC2陶瓷的制备 总被引:4,自引:2,他引:2
Ti3SiC2陶瓷由于具有非常优越的性能而受到广泛关注,但到目前对于反应合成Ti3SiC2的热力学和动力学仍缺乏系统地研究.本文对反应合成Ti3SiC2进行了热力学计算和动力学分析,利用Ti、Si、C混合粉末进行热压,制备了较高纯度的Ti3SiC2陶瓷,并对烧结试样进行XRD和断口SEM分析.热力学计算结果表明:在常用的反应合成Ti3SiC2的材料体系中,Ti-Si-C三元粉末的反应热力学驱动力最大,据此选择Ti、Si、C粉末,按照3:1.2:2的原子比混合作为反应合成Ti3SiC2的原料;动力学分析结果表明:Ti-Si-C三元元素粉末的反应动力学要求必须有较高的升温速度,才能获得Ti3SiC2材料.根据动力学分析结果设计反应合成工艺,利用真空热压获得了纯度达到89%(体积分数,下同)以上的Ti3SiC2材料. 相似文献
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SiC/(W, Ti)C ceramic composites with different content of (W, Ti)C solid-solution were produced by hot pressing. The effect of (W, Ti)C content on the microstructure and mechanical properties of SiC/(W, Ti)C ceramic composites has been studied. Densification rates of the SiC/(W, Ti)C ceramic composites were found to be affected by addition of (W, Ti)C. Increasing (W, Ti)C content led to increase the densification rates of the composites. The sintering temperature was lowered from 2100 °C for monolithic SiC to 1900 °C for the SiC/(W, Ti)C composites. Results show that additions of (W, Ti)C to SiC matrix resulted in improved mechanical properties compared to pure SiC ceramic. The fracture toughness and flexural strength continuously increased with increasing (W, Ti)C content up to 60 vol.%, while the hardness decreased with increasing (W, Ti)C content. 相似文献
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B4C/SiCw陶瓷喷砂嘴的制备及其冲蚀磨损机理研究 总被引:6,自引:0,他引:6
采用热压烧结工艺制备了B4C/SiCw陶瓷喷砂嘴,研究了SiC晶须的含量对B4C/SiCw陶瓷材料性能的影响.以SiC和Al2O3磨料对B4C/SiCw陶瓷喷砂嘴进行冲蚀磨损试验,研究不同磨料对B4C/SiCw陶瓷喷砂嘴冲蚀磨损的影响,分析了其冲蚀磨损机理.结果表明:B4C/SiCw陶瓷喷砂嘴的冲蚀磨损机理主要表现为脆性断裂和磨料粒子对喷嘴的切入所造成的微观切削作用.磨料的硬度和粒度对陶瓷喷嘴的磨损有重要的影响,磨料的硬度和粒度越大,陶瓷喷嘴的磨损速度加快. 相似文献
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以硫粉、锡粉、三硫化二锑为烧结剂,再加入其他辅助原料,利用金属硫化物的低熔点烧结制备陶瓷摩擦材料。研究了原料的不同配比对金属硫化物陶瓷摩擦材料的体积密度、气孔率、力学性能、摩擦性能以及显微结构的影响。硫含量对金属硫化物陶瓷摩擦材料性能有很重要的影响,通过对比寻求较为理想的原料配比,并对其实际应用的可行性进行探讨。 相似文献
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《Ceramics International》2016,42(12):13497-13506
Si3N4/(W, Ti)C graded nano-composite ceramic tool materials with different thickness ratios and number of layers were fabricated by hot pressing technology. The flexural strength, fracture toughness and hardness of the sintered composites were tested and the microstructure and indention cracks were observed. The experiment results showed that the five-layer graded nano-composites with a thickness ratio of 0.2, which were sintered under a pressure of 30 MPa at 1700 °C in vacuum condition for 45 min, had the optimum comprehensive mechanical properties with a flexural strength of 1080.3 MPa, a hardness of 17.64 GPa, and a fracture toughness of 10.87 MPa·m1/2. The formation of elongated β-Si3N4 grains contributes to the favorable mechanical properties. The graded structure can induce residual compressive stress in the surface layer and enhance the mechanical properties. The strengthening and toughening mechanisms are a synergistic effect of intergranular and transgranular fracture, crack bridging and deflection. 相似文献