Microstructure and Oxidation Behavior of ZrB_(2)-SiC Ceramics Fabricated by Tape Casting and Reactive Melt Infiltration  

流延成型结合反应熔渗制备ZrB_(2)-SiC陶瓷及其微观结构与氧化行为研究

作　　者：TAN Min CHEN Xiaowu YANG Jinshan ZHANG Xiangyu KAN Yanmei ZHOU Haijun XUE Yudong DONG Shaoming 谭敏;陈小武;杨金山;张翔宇;阚艳梅;周海军;薛玉冬;董绍明(中国科学院上海硅酸盐研究所,高性能陶瓷和超精密微结构国家重点实验室,上海200050;中国科学院大学材料与光电研究中心,北京100049)

机构地区：[1]State Key Laboratory of High Performance Ceramics and Superfine Microstructure,Shanghai Institute of Ceramics,Chinese Academy of Sciences,Shanghai 200050,China [2]Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China

出　　处：《无机材料学报》2024年第8期955-964,共10页Journal of Inorganic Materials

基　　金：National Key R&D Program of China(2022YFB3707700);Shanghai Science and Technology Innovation Action Plan(21511104800);National Natural Science Foundation of China(52172111);National Science and Technology Major Project(2017-IV-0005-0042);Key Research Program of the Chinese Academy of Sciences(ZDRW-CN-2021-2-2);Science Center for Gas Turbine Project(P2022-B-IV-001-001)。

摘　　要：ZrB_(2)-based ceramics typically necessitate high temperature and pressure for sintering,whereas ZrB_(2)-SiC ceramics can be fabricated at 1500℃using the process of reactive melt infiltration with Si.In comparison to the conventional preparation method,reactive synthesis allows for the more facile production of ultra-high temperature ceramics with fine particle size and homogeneous composition.In this work,ZrSi_(2),B4C,and C were used as raw materials to prepare ZrB_(2)-SiC via combination of tape casting and reactive melt infiltration herein referred to as ZBC ceramics.Control sample of ZrB_(2)-SiC was also prepared using ZrB_(2) and SiC as raw materials through an identical process designated as ZS ceramics.Microscopic analysis of both ceramic groups revealed smaller and more uniformly distributed particles of the ZrB_(2) phase in ZBC ceramics compared to the larger particles in ZS ceramics.Both sets of ceramics underwent cyclic oxidation testing in the air at 1600℃for a cumulative duration of 5 cycles,each cycle lasting 2 h.Analysis of the oxidation behavior showed that both ZBC ceramics and ZS ceramics developed a glassy SiO_(2)-ZrO_(2) oxide layer on their surfaces during the oxidation.This layer severed as a barrier against oxygen.In ZBC ceramics,ZrO_(2) is finely distributed in SiO_(2),whereas in ZS ceramics,larger ZrO_(2) particles coexist with glassy SiO_(2).The surface oxide layer of ZBC ceramics maintains a dense structure because the well-dispersed ZrO_(2) increases the viscosity of glassy SiO_(2),preventing its crystallization during the cooling.Conversely,some SiO_(2) in the oxide layer of ZS ceramics may crystallize and form a eutectic with ZrO_(2),leading to the formation of ZrSiO_(4).This leads to cracking of the oxide layer due to differences in thermal expansion coefficients,weakening its barrier effect.An analysis of the oxidation resistance shows that ZBC ceramics exhibit less increase in oxide layer thickness and mass compared to ZS ceramics,suggesting superior oxidation resistance of ZBZrB_(2)基陶瓷通常需要在高温高压条件下才能烧结致密,而利用反应熔渗Si的方式可在1500℃制得ZrB_(2)-SiC致密陶瓷。相较于常规制备方法,反应制备法更容易获得晶粒细小、成分均匀的超高温陶瓷相。本研究以ZrSi_(2)、B_(4)C和C为原料,通过流延成型结合反应熔渗制备ZrB_(2)-SiC陶瓷(简称ZBC陶瓷)。此外,还以ZrB_(2)和SiC为原料,通过相同的工艺制备了一组ZrB_(2)-SiC陶瓷(简称ZS陶瓷)作为对比样品。对两组陶瓷的微观形貌进行表征,发现ZBC陶瓷中ZrB_(2)相的颗粒尺寸较小且弥散分布在陶瓷中,而ZS陶瓷中ZrB_(2)相的颗粒尺寸较大。在1600℃空气环境中对两组陶瓷进行循环氧化测试,总共循环氧化5次,每次2h。分析两者的氧化行为,发现ZBC陶瓷与ZS陶瓷在氧化过程中表面都会形成玻璃态SiO_(2)-ZrO_(2)氧化层,起到阻隔氧气的作用。不同点在于ZBC陶瓷中ZrO_(2)弥散分布在SiO_(2)中,而ZS陶瓷是大尺寸的ZrO_(2)与玻璃态SiO_(2)共存。在降温过程中,弥散分布的ZrO_(2)能够提高玻璃态SiO_(2)的黏度,抑制其结晶,所以ZBC陶瓷的表面氧化层能够保持致密的结构;而ZS陶瓷氧化层中SiO_(2)大量结晶并与ZrO_(2)共晶反应产生ZrSiO_(4),由于热应力导致氧化层开裂,使其阻隔氧气的作用大大减弱。分析两者的抗氧化性能,发现ZBC陶瓷的氧化层厚度变化与质量增加均小于ZS陶瓷,表明ZBC陶瓷的抗氧化性能优于ZS陶瓷。

关 键 词：ultra-high temperature ceramic ZRB2-SIC oxidation behavior reactive melt infiltration 

分 类 号：TQ174[化学工程—陶瓷工业]