摘要
基于自蔓延高温合成(SHS)技术,在碳钢的铸造过程中,同步合成了厚10mm的TiC-Fe金属陶瓷复合涂层。采用X射线衍射(XRD)确定了合成涂层的相组成,并分别用光学显微镜(OM),扫描电镜(SEM)和电子探针(EPMA)分析了涂层的显微组织及其与钢基体的界面结构。实验结果表明,合成的涂层除表面2mm的区域外,其它部分均具有较致密的结构。而且,涂层中原位合成的TiC颗粒的数量和尺寸均沿涂层的厚度方向逐渐递减,直至与钢基体实现梯度复合。初步认为,浇铸的钢液向Ti-C-Fe预制块中的渗透以及预制块中Fe粉的熔化对上述梯度复合涂层的形成起到了积极的作用。
A Ti-C-Fe preform was pre-placed in a mould cavity and then was directly ignited to bring about the self-propagating high-temperature synthesis (SHS) reaction by the temperature of pouring liquid carbon steel. As a result, a TiC-Fe cermet coating with a thickness of 10 mm was simultaneously synthesized on the steel substrate during its casting. The phase constituents of the synthesized coating were inspected by X-ray diffraction (XRD), and the microstructure of the coating, especially its interfacial structure with the substrate, was analyzed with optical microscopy (OM), scanning electron microscopy (SEM) and electron probe microanalyzer (EPMA). The experimental results show that the coating, except for its outside layer with about 2 mm thickness, has dense microstructure. The amount and the size of the synthesized TiC particles in the coating decrease gradually in the thickness direction, so that a graded composite interface is formed between the coating and the substrate. It is considered that the infiltrations of the poured liquid steel into the preform and the fusion of Fe powders in the preform may make a contribution to the formation of the graded composite coating.
出处
《复合材料学报》
EI
CAS
CSCD
北大核心
2003年第3期64-68,共5页
Acta Materiae Compositae Sinica
基金
国家自然科学基金(50276023)
材料复合新技术国家重点实验室开放基金(9908)
关键词
SHS
铸造
TiC—Fe金属陶瓷涂层
钢基
梯度复合
界面
High temperature operations
Interfaces (materials)
Microstructure
Scanning electron microscopy
Steel castings
Titanium carbide
