反应热压法制备B_4C基复合材料的烧结致密化研究  

Study on densification process of B_4C based compositesby reaction hot pressing

作　　者：杨杰[1] 张守年[2] 祁宇翔[1] 初蕾[3] 刘英才[3] 

机构地区：[1]承德职业学院机电系,河北承德067000 [2]辽东学院装备与材料分院,辽宁丹东118003 [3]中国海洋大学材料科学与工程学院,山东青岛266003

出　　处：《河北科技大学学报》2005年第3期225-229,236,共6页Journal of Hebei University of Science and Technology

基　　金：国家863计划青年基金资助项目(2004AA639680)

摘　　要：通过在B4C中添加Si3N4以及少量的SiC和TiC,在1 820～1 900 ℃,30 MPa的热压条件下反应生成了B4C基轻质复合材料,烧结助剂为(Al2O3+Y2O3).结合材料的断口SEM形貌,分析讨论了烧结致密化过程,结果表明:在相同烧结温度下,随基体相B4C含量的增多,复合材料变得更难烧结;对同成分组成的复合材料来说,随着烧结温度的升高,最终得到的材料致密度有所提高.两步烧结过程中的降温保温阶段,有利于放热反应的彻底进行,使最终复相陶瓷组织中含有少量细小的TiB2 和BN相,同时,放热反应可以维持致密化进程的继续进行,这对于提高复合材料的强度和韧性有利.B4C based composites were made in hot-pressed reaction through introducing Si3N4 and small amount of SiC and TiC into B4C matrix at 1 820～1 900℃ under the pressure of 30MPa, with the sintering additives of （Al2O3 ＋Y2O3 ）. The densification process was analyzed combined with the SEM images of fracture surfaces. At the same sintering temperature, the densification of composites becomes much difficult with the increasing B4C content. For the same components, the density increases with the increase of sintering temperature. The improved densification process should be attributed to the two-step method, reaction heat and grain refinement as well as liquid sintering resulted from additives.

关 键 词：反应热压 B4C复合材料 致密化 两步法烧结 液相烧结 

分 类 号：TB332[一般工业技术—材料科学与工程]