Al粉粒度及其添加量对SiC陶瓷材料结构和性能的影响

以Al粉为烧结助剂,采用无压烧结工艺于1600℃下保温3 h烧制SiC陶瓷材料,研究了不同Al粉粒度及其添加量对SiC陶瓷材料结构和性能的影响.结果表明:Al粉可促进SiC陶瓷材料的烧结和力学性能的提高,同时起抗氧化的作用,且粒度较小的Al粉对其性能提升的幅度较大.当添加4wt;粒度为48μm的Al粉时,SiC陶瓷材料的性能较佳,体积密度和显气孔率分别为2.69 g/cm3和5.8;,显微硬度和抗折强度分别为2790 HV和189 MPa.SiC陶瓷材料烧结性能和力学性能的提高可归因于Al粉的促烧结作用,及其氧化产物Al2 O3和原位生成的少量莫来石分布在SiC颗粒间所起的强化作用.

Effect of Particle Size and Content of Al Powder on the Structure and Properties of SiC Ceramic Materials

SiC ceramic materials were prepared with Al powder as the sintering aid by pressureless sintering at 1600 ℃ for 3 h.The effects of particle size and content of Al powder on the structure and properties of SiC ceramic materialswere studied .The results show that Al powder can improve the sintering and mechanical properties of SiC ceramic materials , it also plays an important role in oxidation resistance , and the Al powder with smaller particle size has a significant effect on that of SiC ceramic materials.When theparticle size and content of Al powder are 48 μm and 4wt%, respectively, SiC ceramic materials can get the best performance .The bulk density and apparent porosity are 2.69 g/cm3 and 5.8%, thenthehardness and flexural strength are 2790 HV and 189 MPa, respectively.The excellent sintering and mechanical properties of SiC ceramic materials can be attributed to the sintering effect of Al powder and the strengthening effects of the in situ formed Al 2 O3 and mullite filling in SiC particles .