【作者】 徐有容； 王德英； 张晓燕；

【Author】 Xu Yourong Wang Deying Zhang Xiaoyan (Shanghai University,School of Materials Science and Engineering,Shanghai,201800,China)

【机构】 上海大学材料学院；

【摘要】 针对高压匀质机柱塞及石油化工用泵轴等应用背景,用激光熔覆、热喷涂表面加工技术,在1Cr18Ni9Ti奥氏体不锈钢等基材上,研究了激光熔覆、热喷涂高硼硅镍基硬面合金、以改善其耐磨、耐蚀性能。本工作通过用各种微观分析手段(SEM、EDAX、XRD、OM)和显微硬度等测试方法,深入研究了激光熔覆、热喷涂高硼硅镍基硬面合金层的微观组织、相组成、元素分布特征和表面硬度特性,并对其进行分析比较,结果示:(1)激光熔覆的硬面合金具有优良的微观组织和综合性能,其组织特征是:在细密均匀的过饱和γNi(Fe)奥氏体固溶体上(过饱和C、B、Cr、Si含量),均匀分布着超细网状碳化物、硼化物、硅化物树枝状晶,形成超细的共晶组织,且合金层与基材呈冶金结合,这是它具有高的硬度和良好的综合性能的基础;(2)热喷涂合金层,其微观组织中未见网状和树枝共晶组织,而只有块状碳化物,硼化物和硅化物,它们对其硬度和综合性能均有不良影响,且合金层与基材结合欠佳。因此,激光熔覆的合金层比热喷涂合金层具有硬度高、综合性能好的优点。更多还原

【Abstract】 Laser cladding adn thermal spray of nickel-hase hardfeing alloy coatings containing high B,Si at the substrate of 1Cr18Ni9Ti austenite stainless steel have been investigated,for the application of high pressure homogenizer,in orfer to improve its resistance to wear and corrosion. The microstructure,phase component,distributive characteristics of elements and surface microhardness of laser cladding and thermal spray of nickel-hase hardfacing alloy coatings have been studied and compared deeperly by using microstructural analysis of SEM,EDAX,XRD and OM,as well measure of microhardness.These results display that:(1)Laser cladding coatings of hardfacing alloy have optimum mocrostructure and properties, the mocrostructure comprises ultrafine and homogeneous dendrites eutectic of carbide,boride and silicate in oversaturatedγNi(Fe)matrix.It possesses optimum metallurgical bond.These are the reasons on optimum properties and resistance to wear in the applications.(2)The microstructure and properties of thermal spray coatings of hardfacing alloy are inferior to laser cladding coatings,the microstructure of thermal spray coatings comprises some block-like carbide,boride and silicate in the matrix,but no dendritic eutectic,and the metallurgical bond is not perfect,these are the reasons on inferior properties.更多还原