复合镀、合金化对铜基电接触材料组织及性能的影响

发布时间：2018-07-07 16:59

本文选题：铜基电接触材料 + 抗电弧烧蚀　；参考：《济南大学》2014年硕士论文

【摘要】：本论文是在实验室原有研究基础上，通过加入不同含量的氧化钇、碳化钨，探究其对铜基电接触材料组织及性能的影响，特别是对材料抗电弧烧蚀的影响；通过对铜粉磁控溅射镀银，研究镀银铜粉抗氧性能及其烧结性能；通过在金属铜中添加不同含量的稀土钇，探究钇对铜性能的影响，特别是对其抗氧化性能的影响；把电阻率法应用于粉末冶金烧结工艺参数的确定。研究结果表明： (1)当添加适量的氧化钇，材料的密度和硬度都得到了提高，氧化钇的添加量为1.5wt.%时，材料密度提高最为显著；氧化钇的添加量为2wt.%时，材料硬度提高最为显著。添加氧化钇有利于阻碍基体铜晶粒的长大，这有利于添加组元更均匀地分布在基体中，能更好地提高材料的电接触性能。通过20000次电弧侵蚀试验表明：添加氧化钇制备的电触头材料的抗电弧烧蚀性能远远优于通用的铜镍合金银复层触头材料，试验后新触头的接触电阻仍能保持稳定的且较低的数值。但是，氧化钇的加入对铜基电触头材料的导电性有不利影响。 (2)研究了电阻率法在粉末冶金烧结工艺参数确定方面的应用。通过实时地测定烧结过程中压坯电阻率的变化，可以快速确定粉末冶金的烧结工艺参数，这种方法对粉末冶金制品的烧结参数的确定具有广泛的适用性。 (3)添加碳化钨可以提高材料的抗电弧烧蚀性能，但是碳化钨对材料的致密度和导电性有不利的影响，添加少量碳化钨可以提高材料的硬度，但其加入量大于6wt.%时，材料的硬度开始下降。对碳化钨颗粒表面进行了磁控溅射镀铜，明显改善了WC/Cu复合界面，添加镀膜碳化钨复合材料的致密度、硬度都比添加未镀膜碳化钨复合材料有明显提高，材料的导电性能也得到改善。 (4)为了改善铜基电接触材料的抗氧化性，通过磁控溅射的方法，在铜粉表面镀一层银膜。通过研究溅射时间与镀银铜粉氧化增重之间关系情况，最终确定了溅射时间为23min。通过把铜粉和镀银铜粉分别压制成坯，然后对比在不同烧结时间下的试样性能情况。研究发现：镀银铜粉制备的试样在不同的烧结时间下，致密度和硬度都高于纯铜粉制备的试样，抗氧化性能也优于纯铜粉制备试样，，但是镀银铜粉制备的试样导电性比纯铜试样差。 (5)在金属铜添加少量稀土钇（少于0.5wt.%），其导电性能增强，添加过量的稀土钇又会使金属铜的导电性能变差。通过抗氧化实验发现：铜钇合金随着稀土钇添加量的增大，试样氧化增重逐渐降低；当稀土钇的添加量为0.1wt.%、0.2wt.%和0.5wt.%时，试样抗氧化性能的提高较为明显；随稀土钇添加量进一步增大时，试样氧化增重的减小趋势缓慢下来。由于添加少量钇对铜组织净化作用，添加0.1wt.%钇时，金属铜的硬度略微下降，减少了铜中固溶的杂质原子。但金属铜中随钇添加量的继续增加，铜钇合金的硬度逐步增大。
[Abstract]:This paper is based on the original research in the laboratory, through the addition of different contents of yttrium oxide, tungsten carbide, to explore its impact on the structure and properties of copper based electrical contact materials, especially on the effect of arc ablation resistance of materials; The oxygen resistance and sintering properties of silver plated copper powder were studied by magnetron sputtering of copper powder, and the effect of yttrium on copper properties, especially its oxidation resistance, was investigated by adding different contents of rare earth yttrium to copper. The resistivity method is applied to determine the sintering parameters of powder metallurgy. The results showed that: (1) the density and hardness of yttrium oxide were increased with the addition of appropriate amount of yttrium oxide, the density of yttrium oxide was the most significant when the addition amount of yttrium oxide was 1.5wt.%, and the addition amount of yttrium oxide was 2wt.%. The hardness of the material is the most obvious. The addition of yttrium oxide is beneficial to the growth of copper grains in the matrix, which is conducive to the more uniform distribution of the added components in the matrix, which can improve the electrical contact properties of the materials. The results of 20000 arc erosion tests show that the arc ablation resistance of the contact material prepared by adding yttrium oxide is much better than that of the common copper-nickel alloy silver clad contact material. The contact resistance of the new contact is stable and low after the test. However, the addition of yttrium oxide has a negative effect on the electrical conductivity of copper-based electrical contact materials. (2) the application of resistivity method to the determination of sintering parameters in powder metallurgy is studied. The sintering parameters of powder metallurgy can be quickly determined by measuring the change of the resistivity of compacted billet during sintering in real time. This method is widely applicable to the determination of sintering parameters of powder metallurgy products. (3) addition of tungsten carbide can improve the arc ablation resistance of the materials, but tungsten carbide has a negative effect on the density and conductivity of the materials. Adding a small amount of tungsten carbide can improve the hardness of the material, but when the addition amount is more than 6 wt.%, the hardness of the material begins to decrease. The WC / Cu composite interface was obviously improved by magnetron sputtering copper plating on the surface of tungsten carbide particles. The density and hardness of WC / Cu composite were obviously improved compared with those of uncoated tungsten carbide composites. (4) in order to improve the oxidation resistance of copper based electrical contact materials, a silver film was deposited on the surface of copper powder by magnetron sputtering. By studying the relationship between sputtering time and oxidation weight gain of silver plated copper powder, the sputtering time was determined to be 23 min. The copper powder and silver plated copper powder were respectively pressed into billets, and then the properties of the samples were compared under different sintering time. It was found that the density and hardness of the samples prepared by silver plating copper powder were higher than those prepared by pure copper powder at different sintering times, and the oxidation resistance of the samples prepared by silver plated copper powder was also better than that prepared by pure copper powder. However, the electrical conductivity of the sample prepared by silver plating copper powder is worse than that of pure copper sample. (5) adding a small amount of rare earth yttrium (less than 0.5 wt.%) to metal copper increases its electrical conductivity, and the addition of excess rare earth yttrium will make the conductivity of metal copper worse. It was found that the oxidation weight of the sample decreased with the increase of the amount of yttrium, and the oxidation resistance of the sample increased obviously when the addition amount of yttrium was 0.1wt.% and 0.5wt.%. With the increase of the amount of yttrium, the decreasing trend of the oxidation weight of the sample slowed down. Due to the purification of copper by adding a small amount of yttrium, the hardness of copper decreases slightly when adding 0.1 wt.% yttrium, which reduces the impurity atoms in copper solution. However, with the increase of yttrium content, the hardness of copper and yttrium alloy increases gradually.
【学位授予单位】：济南大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM501.3

【参考文献】