电接触强化预涂层的制备

发布时间：2018-03-19 01:09

本文选题：粘结技术　切入点：电接触强化　出处：《东华大学》2017年硕士论文　论文类型：学位论文

【摘要】：目前磨损失效导致设备报废的问题相当严重,据统计损坏设备中大约有70%~80%的设备产生了磨损失效的问题。由此可见,重视资源的充分利用节约材料,加强抗磨技术的研究,提高材料抗磨性能降低磨损的工作显得尤为重要。本论文研究内容为探索一种简单高效、成本低廉、涂层质量优越的硬质涂层制备技术,具体方法为采用粘结剂与合金粉末混合成浆料刮涂在工件表面制成预涂层,然后进行电接触强化来获得高性能涂层。首先,分别采用硅酸盐类粘结剂、低熔点金属粘结剂焊锡膏、热固性环氧树脂粘结剂与合金粉末混合制备预涂层再进行电接触强化,得出预涂层采用热固性环氧树脂粘结剂与合金粉末混合制成效果最好;之后又对使用热固性环氧树脂粘结剂制备的预涂层进行了性能改善,在浆料刮涂在工件表面后覆盖合金粉末的方法增强了预涂层的导电性;通过实验确定了粘结剂与合金粉末的最佳配比为1:2;预涂层制备好后在烘干炉中烘干的方法解决了预涂层固化不完全的问题;然后对电接触强化的工艺进行了改进,包括预紧力的设置、预热处理、电接触强化电流的设置、主轴转速与进给速度的设置;分别电接触强化多种合金粉末预涂层,得出电接触强化Ni60-WC预涂层的效果最好;对强化后涂层进行了微观组织观察、涂层与基体交界处元素线扫描、显微硬度的测试,通过分析,涂层组织致密,夹生与孔洞较少,涂层与基体交界处结合良好,在界面处发生了元素扩散,产生了冶金结合,涂层的硬度由于涂层粉末混合不均匀在748HV到862HV之间波动。
[Abstract]:At present, the problem of equipment scrapping caused by wear and tear failure is quite serious. According to statistics, about 70% of the equipment damaged has caused the problem of wear failure. It can be seen from this that we should attach importance to the full use of resources, save materials, and strengthen the research on anti-wear technology. It is very important to improve the wear resistance of materials and reduce the wear. In this paper, we aim to explore a simple, efficient, low cost and superior coating quality preparation technology for hard coatings. The specific method is to use binder and alloy powder to form slurry to make precoating on the surface of workpiece, and then electric contact strengthening to obtain high performance coating. First, silicate binder is used respectively. Low melting point metal binder solder paste thermosetting epoxy resin binder and alloy powder were mixed to prepare precoating and then electrical contact strengthening. The results showed that the best effect was obtained by mixing thermosetting epoxy resin binder with alloy powder. Then the precoating prepared by thermosetting epoxy resin binder was improved, and the conductivity of the precoating was enhanced by coating the alloy powder on the surface of the workpiece by scraping the slurry. The optimum ratio of binder and alloy powder was determined to be 1: 2 by experiment. The method of drying precoating after preparation was solved the problem of incomplete curing of precoating. Then the process of electric contact strengthening was improved. It includes setting of pretightening force, preheating treatment, setting of electric contact strengthening current, setting of spindle speed and feed speed, and electric contact strengthening of various alloy powder precoating, the result shows that electric contact strengthening Ni60-WC precoating is the best. The microstructure of the strengthened coating was observed. The results showed that the interface between the coating and the substrate was linear scanning and the microhardness was measured. Through analysis, the microstructure of the coating was dense, the clamping and porosity were less, and the interface between the coating and the substrate was good. Element diffusion occurs at the interface and metallurgical bonding occurs. The hardness of the coating varies from 748 HV to 862 HV due to the uneven mixing of the coating powder.
【学位授予单位】：东华大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TG174.4

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