高致密度、复杂形状SiC陶瓷的组合热压烧结技术

摘要

A novel combined hot pressing sintering technology was proposed,and the SiC ceramic with complex inner cavity was prepared successfully by using graphite as the mold core material.The results show that when the solid content of both SiC and graphite slurries was 50vol%,the density of SiC ceramic after sintering was the highest and the radial shrinkage ratio difference between SiC and graphite was minimum.The graphite mold core can be removed easily and the inner cavity of the obtained SiC ceramic was smooth and complete.The relative density of SiC ceramic was 98.5% and flexural strength was 580 MPa.%提出了一种组合热压烧结新工艺,以石墨为型芯材料成功制备出具有复杂内部型腔的SiC陶瓷.结果表明:当石墨和SiC浆料固相含量均为50%(体积分数)时,烧结后SiC陶瓷的密度最高且与石墨的径向收缩率差值最小;石墨型芯易于去除,得到的SiC陶瓷内部型腔平滑且完整,相对密度高达98.5%,抗弯强度达到580 MPa.