摘要
基于Ti与C自蔓延高温合成反应原理,利用SHS(自蔓延高温合成)辅助激光熔敷技术,通过优化激光功率、扫描速度、光斑直径、光斑搭接率等工艺参数,成功地在LY12铝合金基体表面制备出TiCNi功能梯度金属陶瓷基复合材料涂层。显微组织分析、能谱分析和X射线衍射分析表明,熔合层为Ni-Al金属间化合物。涂层组织致密而纯净,各层之间成分彼此扩散,无明显的界限,为完全的冶金结合。反应热粗化了临近界面基体的晶粒度;解释了涂层合成过程和结合机理。涂层的形成是Ti与Ni、Ti与C、Ni与Al之间的一系列SHS反应的结果。不同温度下的热震性测试结果表明,涂层的热震性能优良。
Based on the principle of the self-propagating high-temperature synthesis （SHS） reaction of Ti and C powders, a Ti CNi cermet composite coating was prepared successfully on LY12 alloy substrate by means of laser cladding. The good technical parameters such as laser power, scanning velocity, beam diameter, overlap ratio and so on were gotten. The OM, XRD, EDS techniques were employed to study the phases of the coating. The results show that the top coating is a layer of TiCNi, below which is the Ni-A1 intermetallic fusion layer and the substrate, and the coating＇s microstructure is dense and pure. Elements are diffused mutually at both sides of the interface and a metallurgical bonding interface. The heating of the reaction coarsens the grain size of the substrate near the interface. The formation mechanism of the layer is explained. It involves a series of SHS reactions, including the reactions between Ti and Ni, Ti and C, Ni and A1. Good interfacial bonding is achieved at the fusion layer, TiCNi interface and the fusion layer/ LY12 alloy substrate. The thermal shock experiment was employed to study the thermal shock properties of the coating at different elevated temperature. The results show that the thermal shock property of the coating is fine.
出处
《热加工工艺》
CSCD
北大核心
2009年第10期131-134,共4页
Hot Working Technology
基金
国家自然科学基金资助项目(50675222
50575226)
作者简介
陈威（1957-），男，黑龙江佳木斯人，研究员，博士，主要从事自蔓延高温合成技术研究与半固态金属加工技术交叉学科研究。电话：010-66717657；E-mail：zgychenwei@sina．com
