共查询到19条相似文献,搜索用时 93 毫秒
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直流和脉冲Ni-ZrO2纳米复合电铸层显微硬度的研究 总被引:2,自引:0,他引:2
利用SEM分析了纯镍电铸层,以及用直流和脉冲工艺所制备纳米复合电铸层的表面形貌,分别研究了影响直流和脉冲纳米复合电铸层显微硬度的各种因素,同时对纳米复合电铸层的强化机理进行了探讨.结果表明,纳米复合电铸层的表面形貌不同于纯镍电铸层,并且其显微硬度得到明显提高.纳米复合电铸层的强化机理主要是细晶强化机制、弥散强化机制和高密度位错强化机制. 相似文献
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以镀银层抗变色特性为主要指标,优选了光亮镀银的双向脉冲参数,并与直流光亮镀银进行了比较,脉冲镀银层的抗变色特性优于直流电镀。 相似文献
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通过间歇式抗高温氧化实验,建立了纯镍电铸层和N i-ZrO2纳米复合电铸层高温氧化动力学模型,分析了电铸层表面和横截面的形貌,测定了电铸层的组织结构。结果表明,N i-ZrO2纳米复合电铸层抗高温氧化性能明显优于纯镍铸层,复合电铸层表面生成的氧化膜晶粒细小且致密,并且该氧化膜较薄,产生的内应力较小,与复合电铸层的黏附性较好。 相似文献
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Ni-ZrO2纳米复合电铸层耐蚀性的研究 总被引:5,自引:0,他引:5
用静态浸泡实验法研究了镍镀层和Ni-ZrO2纳米复合电铸层在质量分数分别为10% HCl溶液和10% H2SO4溶液中的耐蚀性.用SEM观察了各种样品腐蚀后的表面形貌,分析了纳米ZrO2微粒复合量对复合电铸层耐蚀性的影响,同时对纳米复合电铸层的腐蚀机理进行了初步探讨.结果表明,脉冲纳米复合电铸层的耐蚀性明显优于相同条件下制备的镍镀层,镀液中纳米ZrO2悬浮量对提高纳米复合电铸层耐蚀性有一定程度的影响. 相似文献
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通过正交试验研究了工艺参数对铸铜层性能的影响。结果表明:电铸铜工艺在景观雕塑制作领域有其独特优势。依据景观雕塑使用条件,在保证铸铜层硬度的前提下,确定了硫酸铜240g/L、硫酸60g/L、电流密度4A/dm~2、温度20℃为最佳的电铸铜工艺条件;在保证铸铜层拉伸强度的前提下,确定了硫酸铜220g/L、硫酸70g/L、电流密度6A/dm~2、温度20℃或30℃为最佳的电铸铜工艺条件;控制电流密度在6A/dm~2左右,铸铜层的硬度与拉伸强度良好。 相似文献
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电铸技术具有良好的复制性、加工方便、成本比传统金属模具低60%、劳动强度低等优点,现已被大家所认识和应用.本文详细介绍了电铸技术的发展概况、电铸原理及各种因素对电铸的影响. 相似文献
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This paper describes an experimental and theoretical study of the effects of different types of waveform on the grain size and the hardness of nickel electroforms in pulse current electroforming. The highest hardness value and the finest grain size were obtained using a ramp-down waveform with relaxation time. The experimental results show that compared with the conventional rectangular waveform and with relaxation time, the hardness value can be improved by about 28% when a ramp-down waveform, also with relaxation time, is used. These results are supported by theoretical predictions and the study of the surface morphology of the electroforms by scanning electron microscopy. 相似文献
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采用电铸技术制造定向反射镜芯模,与精密机械加工方法相比,电铸法具有加工精度高,能完全复制形状复杂而且具有不同粗糙度的表面,加工成本低,适于大批量生产,介绍了电铸法制造定向反射镜芯模的表面准备以及电铸工艺中的一些特殊问题。 相似文献
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M.S. Chandrasekar 《Electrochimica acta》2008,53(8):3313-3322
A review on pulse and pulse reverse techniques for electrodeposition have been attempted. Pulse electrodeposition (PED) of some metals and alloys are reported. The effects of mass, transport, electrical double layer pulse parameters and current distribution on surface roughness and morphology are presented. Applications, advantages and disadvantages of PC and PRC techniques are discussed along with theoretical aspects and mechanism. 相似文献
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近年来脉冲电镀发展概况 总被引:9,自引:1,他引:9
综述了80年代末我国双脉冲电镀电源开发成功以来,国内外脉冲电镀发展概况,如脉冲单金属电镀、脉冲合金电镀及复合电镀、脉冲阳极氧化等。简单介绍了脉冲电源在其它领域中的应用。 相似文献
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脉冲电解可以调解电流密度、电流的通断时间、脉冲频率等多个参数,为控制金属沉积层的质量和沉积速度提供了有力的手段.介绍了近年来国内外有关脉冲电解的主要研究方向. 相似文献
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Zhong Zhao Pengcheng Zhu Linchu Yang Yaoxiang Geng 《Journal of Adhesion Science and Technology》2019,33(3):301-313
Adhesion plays a critical role in the reliability of the micro devices in MEMS. However, the quality of the micro devices fabricated by electroforming technology is influenced by the poor adhesion performance. In order to improve the poor adhesion performance, from the view of the dislocation density, this paper investigates the effect of the current density on the adhesion originally. To research the effect of the dislocation density, electroforming experiments were processed under two different current densities. The dislocation density and the compressive stress of the electroforming layer was measured by XRD method. The dislocation was observed by TEM method. The adhesion strength was tested by scratch test. The experimental results show that the small current density reduces the dislocation density and the compressive stress, increases the adhesion. The mechanisms are that the small current density reduces the dislocation density. The low dislocation density can reduce the compressive stress and increase the adhesion. This work can improve the adhesion of the electroforming layer. 相似文献