【摘要】 利用放电等离子烧结技术（SPS）在不同的烧结温度下对ZrB₂-SiC超高温陶瓷进行烧结,研究了烧结温度对烧结体致密化的影响。结果表明,在烧结温度分别为1650℃、1750℃、1850℃和1950℃,升温速度为200℃/min,保温时间为1 min,压力为50 MPa时,随着烧结温度的提高,烧结体的致密度呈上升趋势。当烧结温度高于1850℃时,烧结体的致密化过程明显加剧;通过对不同烧结温度下制得的试样的XRD谱图分析发现.当温度高于1850℃时ZrB₂-SiC陶瓷中的SiC相会发生3C相到4H相的转变,这可能就是当烧结温度高于1850℃时烧结体致密度会急剧上升的原因。更多还原

【Abstract】 Ultra-high temperature ceramics ZrB₂-SiC were prepared at 1650℃,1750℃,1850℃and 1950℃sintering temperature,under 50MPa sintering pressure,at 200℃/min heating rate and for 1 minute holding time by spark plasma sintering technique（SPS）.The effect of sintering temperature on densification was mainly studied.The relation curve of densities and sintering temperature showed the relative densities increased with sintering temperature increasing.When the sintering temperature was higher than 1850"C,the densification rate increased sharply.X-ray diffraction patterns of sintered samples at various sintering temperature showed when the sintering temperatures was higher than 1850℃the crystallographic form of SiC can change from 3C to 4H,and maybe this is the reason why densification rate increased sharply.更多还原