摘要
采用粉末烧结结合浸渗法制备高体积TiB2含量的双连续81.6%TiB2/(Cu,Ni)复合材料,并利用扫描电镜(SEM)、透射电镜(TEM)和物相测定(XRD)对双连续复合材料的微观组织形貌进行了观测,表明复合材料中陶瓷骨架相和金属相在各自空间均形成三维网络结构且界面结合牢靠。用交流等离子电弧加热器对试件表面瞬时加热来考核复合材料的抗热冲击和抗烧蚀行为。结果表明,材料在电弧急剧加热和冷却过程中均没有出现"热裂"现象,烧蚀后材料的微观组织分析表明,金属(Cu,Ni)相在材料烧蚀区-过渡区-基体区存在明显的梯度分布,分析了高温下金属相"发汗冷却"行为和防热机理。
In this paper, TiB2/（Cu, Ni） interpenetrating phase composites（IPCs） with the TiB2 content of 81.6% were prepared by high temperature sintering and melt-infiltration process. The microstructure, interfacial bonding and ablated surface or cross sections of the composites were investigated by SEM, TEM and XRD. The results show that ceramic skeleton phase and metal phase of the composites formed three-dimensional network structure in their own space, respectively, and the interface bonding is reliable. The thermal ablation behavior of TiB2/（Cu, Ni） IPCs was conducted by alternating plasma arc heater. The results show that the ablation mechanism of TiB2/（Cu,Ni） IPCs is mainly transpiration cooling of metal phase at elevated temperature coupled with oxidation ablation. The ablated morphology of cross section includes three parts： ablated region, transition region and matrix region. The properties measurement and microstructure analysis after ablative experiment reveal a clue of redistribution of infiltrated Cu alloy so as to analyze and explain the functioning of transpiration cooling and thermal protection mechanism at super high temperature.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2007年第A01期692-695,共4页
Rare Metal Materials and Engineering
基金
国家自然科学基金重点项目(90505015)
