放电等离子烧结制备高纯Ta_(2)AlC陶瓷及其高温氧化行为  

Preparation and High-temperature Oxidation Behavior of High Purity Ta_(2)AlC Ceramics Prepared by Spark Plasma Sintering

作　　者：胡聪 应国兵[1] 刘璐 孙铖 文栋 张建峰[1] 张晨[1] 王香 王乘[1] HU Cong;YING Guobing;LIU Lu;SUN Cheng;WEN Dong;ZHANG Jianfeng;ZHANG Chen;WANG Xiang;WANG Cheng(College of Mechanics and Materials,Hohai University,Nanjing 211100,China;Key Laboratory of Superlight Materials&Surface Technology of Ministry of Education,Harbin Engineering University,Harbin 150001,China)

机构地区：[1]河海大学力学与材料学院,南京211100 [2]哈尔滨工程大学超轻材料与表面技术教育部重点实验室,哈尔滨150001

出　　处：《材料导报》2021年第12期12044-12048,共5页Materials Reports

基　　金：国家自然科学基金(11872171);中央高校基本业务费(B200202117)。

摘　　要：以Ta粉、Al粉和炭黑粉为原料,利用自蔓延高温合成、无压烧结和放电等离子烧结组合工艺,成功制备了高纯Ta_(2)AlC块体陶瓷,研究了放电等离子烧结制备的Ta_(2)AlC块体的微观形貌与性能。制备的Ta_(2)AlC块体的硬度、弯曲强度和断裂韧性分别为5.6 GPa、510 MPa和6.16 MPa·m^(1/2)。放电等离子烧结工艺升温速率快、烧结时间短、制备的陶瓷晶粒细小,细晶强化效果明显,使得块体陶瓷有明显的高硬度和强度。Ta_(2)AlC陶瓷在700~900℃空气中恒温氧化时,表现出线性氧化动力学特征,氧化层的主要成分从700℃的Ta_(2)O_(5)逐渐转变成800~900℃时的Ta_(2)O_(5)和AlTaO_(4)。High purity and bulk Ta_(2)AlC ceramics had been synthesized by self-propagating high-temperature synthesis,pressure-less sintering and spark plasma sintering,using Ta,Al and carbon black powders as raw materials.Microstructures and properties of the as-fabricated Ta_(2)AlC ceramics were investigated.The Vickers hardness,flexural strength and fracture toughness of the as-fabricated bulk Ta_(2)AlC ceramics are 5.6 GPa,510 MPa and 6.16 MPa·m^(1/2),respectively.The fast heating rate,short sintering time and fine grain formation in the spark plasma sintering resulted in a fine-grain strengthening effect which led to the high hardness and strength.The Ta_(2)AlC ceramics oxidized at the temperature range of 700-900℃showed a linear oxidation kinetics trend.When the Ta_(2)AlC ceramic was oxidized at 700℃for 15 h,the oxidation layer of the Ta_(2)AlC was mainly composed of Ta_(2)O_(5).And the oxidation products would become Ta_(2)O_(5)and AlTaO_(4)while the oxidation temperature was risen up to 800-900℃.

关 键 词：Ta_(2)AlC 放电等离子烧结 力学性能 氧化行为 

分 类 号：TB321[一般工业技术—材料科学与工程]