ZrB_(2)–SiC–Zr_(2)Al_(4)C_(5)复相陶瓷烧结反应机理与高温氧化行为  

Reaction Mechanism and High-Temperature Oxidation Behavior of Reactively Sintered ZrB_(2)–SiC–Zr_(2)Al_(4)C_(5)Composite Ceramics

作　　者：郭启龙 华亮 刘荣浩 应豪 李蕾蕾 王璟 GUO Qilong;HUA Liang;LIU Ronghao;YING Hao;LI Leilei;WANG Jing(School of Civil Engineering,Northwest University for Nationalities,Lanzhou 730124,China;Key Laboratory of New Building Materials and Building Energy Efficiency of Gansu Province,Lanzhou 730124,China)

机构地区：[1]西北民族大学土木工程学院,兰州730124 [2]甘肃省新型建材与建筑节能重点实验室,兰州730124

出　　处：《硅酸盐学报》2023年第3期706-720,共15页Journal of The Chinese Ceramic Society

基　　金：甘肃省自然科学基金(20JR5RA510);国家自然科学基金(52162011);中央高校基本科研业务费专项资金项目(31920210011)。

摘　　要：ZrB_(2)基复相陶瓷在超高温领域有着重大应用潜力,但其韧性低、抗氧化性差限制了其实际应用。以Zr、B4C、Al、C和Si粉为原料,采用反应放电等离子体烧结制备出ZrB_(2)–SiC–Zr_(2)Al_(4)C_(5)复相陶瓷,研究了反应过程和反应机理,探究了Zr_(2)Al_(4)C_(5)含量和氧化温度对复相陶瓷高温氧化行为的影响,揭示了其抗氧化机制。结果表明:900℃时,B4C和Zr反应开始生成ZrB_(2);1100℃开始生成SiC;1400℃时反应初期形成的Zr3Al3C5与ZrC及Al4C3生成了Zr_(2)Al_(4)C_(5);但随着温度继续升高Zr_(2)Al_(4)C_(5)则会转化为Zr3Al4C6。复相陶瓷氧化后主要物相为ZrO_(2)、ZrSiO_(4)和铝硅酸盐以及SiO_(2)玻璃相;随着Zr_(2)Al_(4)C_(5)含量的增加,氧化层表面呈现出凹凸不平、疏松多孔,存在明显的长条状晶粒和不均匀分布的玻璃相。本工作为深化对ZrB_(2)–SiC基复相陶瓷的高温氧化行为的理解提供了实验依据,为开发高性能ZrB_(2)–SiC基高温复相陶瓷提供了实验与理论支持。ZrB_(2)-based composite ceramics have great potential for applications at ultra-high temperatures,but the low toughness and poor oxidation resistance of them limit their practical applications.In this work,the Zr,B4C,Al,C and Si raw powders were used to prepare ZrB_(2)–SiC–Zr_(2)Al_(4)C_(5)composite ceramics by reactive spark plasma sintering.The reaction processes and mechanism were studied.The effects of Zr_(2)Al_(4)C_(5)content and oxidation temperature on high-temperature oxidation behavior of multiphase ceramics were investigated for revealing the anti-oxidation mechanism.The results indicated that the B4C reacted with Zr to form ZrB_(2)at900℃,and then the SiC formed at 1100℃.At 1400℃,the Zr_(2)Al_(4)C_(5)formed from the reaction of Zr3Al3C5,ZrC and Al4C3which formed at the early initial reaction stage.And the Zr_(2)Al_(4)C_(5)transformed into Zr3Al4C6with further increasing temperature.The main phases of the composite ceramics after oxidation are ZrO_(2),ZrSiO_(4),aluminosilicate and SiO_(2)glass.With increasing Zr_(2)Al_(4)C_(5)content,the surface of the oxide layer of the composite ceramics became uneven,loose and porous,while obvious long strip grains and inhomogeneous distribution of glassy phases were also observed.This study not only provides a new experimental reference for in-depth understanding of the high-temperature oxidation behavior of ZrB_(2)–SiC based multiphase ceramics,but also provides new experimental and theoretical support for developing high-performance ZrB_(2)–SiC based high-temperature composite ceramics.

关 键 词：二硼化锆基复相陶瓷 烧结 反应机理 氧化行为 

分 类 号：TQ174.75[化学工程—陶瓷工业]