【摘要】 利用流延法成膜和热压烧结工艺制备出了ZrB2-SiC层和石墨层交替排列、层厚均匀、界面清晰的ZrB2-SiC/C层状复合陶瓷。采用循环氧化法对ZrB2-SiC和ZrB2-SiC/C层状复合陶瓷在1000℃及1300℃空气中的氧化动力学曲线进行了研究。结果表明:在1000℃氧化增重时,ZrB2-SiC/C层状复合陶瓷在氧化反应初期表现为氧化增重,随着时间的增加,表现为氧化减重。在1300℃时,ZrB2-SiC/C层状复合陶瓷由于基体层ZrB2-SiC和弱夹层石墨相的氧化规律的相互叠加,使得其氧化增重曲线表现为抛物线规律。由XRD分析及扫描电镜观察发现,1300℃氧化15 h后,试样中不存在弱夹层石墨相,由于石墨相的挥发,材料残留孔隙。更多还原

【Abstract】 Laminated ZrB2-SiC ceramic with graphite interface layers was successfully prepared by doctorblade casting process,laminating and hot pressing.Circulated oxidation method was used to test the high temperature oxidation property of composites in the temperature of 1000 ℃ and 1300 ℃ and the oxidation kinetics curves were studied.At 1000 ℃,in the preliminary stage,the laminated ZrB2-SiC ceramic provided mass gain,as time increased it provided mass loss.At 1300 ℃,because the weak intercalation and the substrate layer stack with each other,the oxidation weight increase curve for the composite followed a para-linear law.The XRD analysis and SEM abservation showed that there was no graphite exit after oxidation at 1300 ℃ for 15 h.And because the volatilization of graphite,there were much pores remained.更多还原