摘要
以钇铝石榴石(yttriumaluminumgarnet,YAG)为烧结助剂,通过无压烧结工艺制备了ZrB2-SiC复相陶瓷。研究了复相陶瓷的相组成、抗烧蚀性能以及烧结助剂含量、烧结温度对复相陶瓷力学性能和显微结构的影响。结果表明:复相陶瓷的物相组成主要为ZrB2,SiC和少量玻璃相;添加YAG或提高烧结温度能使材料的晶粒显著长大,并显著提高材料的相对密度和力学性能。当YAG含量为9%(质量分数),烧结温度为1800℃时陶瓷的相对密度为97.1%、Rockwell硬度HRa为88、弯曲强度为296MPa、断裂韧性为5.6MPa·m1/2。复相陶瓷具有优异的超高温抗烧蚀性能,在2800℃烧蚀30min,烧蚀率仅为0.001mm/s,烧蚀后的显微结构呈现复杂的多层结构。
Zirconium diboride-silicon carbide （ZrB2-SiC） composites were prepared by pressless sintering with yttrium aluminum garnet （YA（3） as sintering additive. The phase compositions of ZrB2-SiC composites, the properties of ablation resistance and the effects of the additive contents and sintering temperature on the mechanical properties and microstructure of composites were investigated. The results show that the phase compositions consist of ZrB2, SiC and a trace of glass phase. Obvious growth of the grains in the materials, higher relative density and better mechanical properties were achieved due to increased YAG content or higher sintering temperature. With a YAG content of 9%（in mass）, the composites has a relative density of 97.1%, Rockwell hardness HRa of 88, bending strength of 296 MPa, and fracture toughness of 5.6 MPa·m1/2 at the sintering temperature 1 800 ℃ .The composites has excellent properties of ablation resistance at ultrahigh temperatures, and a very low ablation rate of 0.001 mm/s after ablation for 30 min at 2 800 ℃. The composites also has a complicated multi-layer microstructure.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2006年第8期1017-1021,共5页
Journal of The Chinese Ceramic Society
关键词
无压烧结
硼化锆基碳化硅复相陶瓷
相组成
力学性能
显微结构
烧蚀
pressless sintering
zirconium diboride-silicon carbide composites
phase compositions
mechanical properties
microslructure
ablation
