微弧火花沉积制备不锈钢柱状微结构表面  

Fabrication of Stainless Steel Microstructure Surface by Electro-spark Deposition

作　　者：王维夫[1,2] 谢剑舟 张步康 阮文豪 韩超[1,2] 

机构地区：[1]浙江工业大学机械工程学院,杭州310014 [2]浙江工业大学化工机械设计研究所过程装备及其再制造教育部工程研究中心,杭州310032

出　　处：《表面技术》2017年第5期159-164,共6页Surface Technology

基　　金：国家自然科学基金项目(51105340);浙江省自然科学基金资助项目(LY14E050008)~~

摘　　要：目的探索新型表面微结构的制备方法。方法采用微弧火花沉积工艺在304不锈钢基体表面,制备出了奇特的"柱状"微结构表面,并使用扫描电镜、光学显微镜、硬度计等对该微柱体的表面形貌、截面特征和显微硬度等进行了初步分析。结果微柱体呈近似有规律的分立状分布,微柱体间距约为0.8~1.2 mm,直径约为300~500μm。微柱体为堆叠状生长,有典型的分层特征,微柱体之间存在生长中的竞争性行为。从微柱体截面来看,单个脉冲沉积薄层的典型厚度大约为15~20μm,微柱体中单个沉积子薄层一般呈中间厚、两侧薄的类透镜状形态。微柱体的平均硬度约为320HV左右,略低于结合界面附近的基体硬度(~340HV)。结论微弧火花沉积的单点、高频率的技术特性是形成此类表面的重要因素,放电沉积中的竞争性机制是导致微柱体成形的直接原因。The work aims to study preparation methods of novel surface microstructure. A special “columnar” microstructure surface was prepared on 304 stainless steel substrate by means of micro-arc spark deposition. Scanning electron microscope （SEM）, optical microscope （OM） and hardness tester were applied to preliminary analysis of morphology, section features and microhardness of the micro-columns. Those micro-columns obtained by ESD were distributed separately and regularly at the distance of nearly 0.8~1.2 mm. Diameter of the micro-columns ranged from 300 to 500 μm. A further observation indicated that rivalrous behaviors were present in the growth between different micro-columns exhibiting typical overlapping characteristics and growing in stacked form. Seen from cross section of the micro-column, thickness of a single pulse deposition film was about 15~20 μm, and single layer in the micro-column was generally in a lenslike form （thick in the middle and thin on both sides）. Average hardness of the deposited micro-columns was nearly 320HV, slightly lower than substrate strength near bonding interface （~340HV）. Formation of such surfaces can be partly attributed to ESD technical features including single point and high frequency characteristics. The competing mechanism in discharge deposition directly leads to the formation of micro-columns.

关 键 词：微弧火花沉积 表面微结构 不锈钢 微柱体 机制 

分 类 号：TG178[金属学及工艺—金属表面处理]