共查询到19条相似文献,搜索用时 125 毫秒
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在电刷镀过程中,影响镀层质量的因素很多,实践过程中不可避免地要出现一些质量上的问题。其中镀层与基体金属的结合强度就是衡量镀层质量的重要指标之一。本文通过对镀层与基体电化学结合机理的探讨,提出了提高镀民基体结合强度的途径和方法。 相似文献
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利用低温镀铁工艺,以B4C的粒径、B4C的质量浓度及FeCl2·4H2O的质量浓度为3个因素进行正交试验。阐述了各因素对镀层性能的影响规律,并针对所遇到的问题提出了解决方案。结果表明:影响镀层耐磨性的因素顺序为B4C的质量浓度B4C的粒径FeCl2·4H2O的质量浓度;影响镀层厚度的因素顺序为FeCl2·4H2O的质量浓度B4C的粒径B4C的质量浓度;影响镀层显微硬度的因素顺序为B4C的质量浓度B4C的粒径FeCl2·4H2O的质量浓度;调整pH值能够获得规整的镀层外观;镀液中无微粒电镀20min后,再进行有微粒电镀,可显著提高镀层与基体的结合强度。 相似文献
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就采用忆刷镀技术进行修复、强化或保护的整个过程而言,电刷镀的质量应包括电刷镀作业本身的质量,镀层在加工过程中的质量和镀层在使用过程中的质量等。本文准备就电刷镀作业本身的质量和与镀层质量有关的加工问题进行探讨。由镀作业本身质量应该包括镀层与基体的结合强度,镀层的厚度控制以及镀层的性能是否达到预定的指标等。 相似文献
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如何提高硬铬镀层的结合力 总被引:3,自引:0,他引:3
本文从理处和实践上总结了提高硬铬镀层结合力的方法。笔者认为因为在镀铬层的结合力试验中,镀铬层的剥离不仅可能发生在基体金属和镀层的界面上,也可能由于镀层本身的破坏所产生,或者二者同时发生。因此影响镀铬层的结合的因素就不只是来自镀前的基体准备方面,而且必须考虑影响镀铬层“内部结合力(镀层强度)的一切电镀因素。本文阐明了基体金属材料,镀前加工方法、镀液中的杂质、操作条件以及镀铬过程的工艺操作方法对镀铬层结合力的影响,并提出了提高硬铬镀层结合力的有效方法。 相似文献
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表面涂层与基体间的界面结合强度及其测定 总被引:16,自引:0,他引:16
阐述了涂层与基体间的界面结合机理,分析了结合界面的类型、影响界面结合强度的因素以及改善涂层与基体间界面结合强度的途径.并介绍了涂层结合强度的测量方法. 相似文献
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接插件镀金、镀银层变色原因及防变色措施 总被引:4,自引:1,他引:3
分别探讨了接插件镀金和镀银层变色的原因.镀金层的变色原因如下:基体质量不符合要求,产品的设计及电镀工艺存在缺陷(包括产品前处理工艺、金阻挡层镀液体系的选择、镀液的维护、电镀工艺参数的选择和电镀方式等的不妥当),镀后处理不力,产品使用环境的差异等.镀银层变色的原因如下:基体形状复杂且其表面粗糙度高,电镀工艺不完善,包装方式不当,产品使用环境差异等.提出了镀层的防变色措施:提高基体质量,减少设计缺陷,改进电镀工艺,加强镀后工序管理,根据产品的使用环境对其制定不同的质量要求等。 相似文献
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通过高温热氧化的方法,在AIN陶表面形成一薄层AI2O3作为过渡层,成功地将铜与AIN陶瓷键合在一起,研制出性能优越的AIN陶瓷覆铜基板。研究了AIN热氧化时间及温度对键合质量的影响,提出子较佳的儿得的键合力可达110N/cm,同时,运用扫描电镜(SEM0、电子能谱(EDX)对键合结构作了分析和研究。AIN衬底上的氧化物相对键合过程中上重要作用。 相似文献
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Microstructure and bonding strength of tin-based Babbitt alloy on ASTM 1045 steel by MIG arc brazing
Mingzhen Wei Kai Sun Xiaoli Zhang Cheng Zhang Zhenhua Chen 《Journal of Adhesion Science and Technology》2018,32(19):2150-2161
The effect of composition of welding wires on the interfacial microstructure and the bonding strength of Babbitt alloys and steel substrate has been studied. A cladding of Sn-based Babbitt alloys was obtained on the surface of medium carbon steel by MIG arc brazing. The microstructure of Babbitt alloys and the interfacial microstructure of the interface between Babbitt alloys and steel substrate have been systematically investigated. The bonding strength of Babbitt and steel substrate has been collected according to the destructive testing method of the bimetallic bonding strength of sliding bearing. Among the three samples, the BW8-4 and steel substrate without no SnSb segregation had the highest bonding strength (83.07 MPa).The reason for the enhancement of the bonding strength was discussed. The IMC layers were harder than the α-Sn matrix so that they can effectively prevent the crack between generating and expanding at the joint part. Then, the bonding strength can be enhanced a lot. However, in samples obtained by BW11-6 and BW8-8, the segregated SnSb phase near the junction which was hard and fragile would result in the concentration of stress. And the SnSb would also lead to the occurrence of brittle fracture in the segregation. So that the bonding strength had been greatly reduced. 相似文献
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Bassam A. Tayeh M.A. Megat Johari M.M. Ratnam 《Journal of Adhesion Science and Technology》2013,27(16):1790-1810
The bonding that exists between the old concrete and the new concrete depends largely on the quality of substrate surface preparation. The accurate representation of substrate surface roughness can help determine very precisely the correct bonding behavior. In this work, an experimental investigation was carried out to quantify the normal concrete (NC) substrate roughness parameters and evaluate their relationship with the bonding performance of ultra high-performance fiber concrete (UHPFC), used as a repair material. The bond strength was quantified based on the results of the pull-off test, splitting cylinder tensile test, and the slant shear test. Three types of NC substrate surface preparation were used: as-cast (without surface preparation) as reference, wire-brushed, and sand-blasted (SB); the roughness of which was determined using an optical three-dimensional (3D) surface metrology device (Alicona Infinite Focus). It was observed from the result of the pull-off test that failure occurred in the substrate, even though adequate substrate surface roughness was provided. Moreover, analysis of the splitting cylinder tensile and slant shear test results showed that the substrate surface preparation method had a significant influence in bonding strength between UHPFC and the NC substrate. The composite UHPFC/NC substrate having a SB surface behaved closely as a monolithic structure under splitting and slant shear tests. An excellent correlation (R 2?>?85%) was obtained between the substrate roughness parameters and the results of the splitting cylinder tensile and slant shear tests. 相似文献
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针对水利水电混凝土工程常处于潮湿状态的特点.介绍了应用于潮湿混凝土基材的喷涂聚脲弹性体涂层的粘接性能,试验结果表明,SK型表面处理剂与潮湿混凝土基材粘接强度能达到5.0MPa.施用表面处理剂后再喷涂聚脲弹性体涂层粘接强度能达到2.5MPa。 相似文献
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研究了羟基磷灰石粉体粒径、粉体预烧温度、陈化时间、分散溶剂、悬浮液固含量对羟基磷灰石悬浮液稳定性的影响,通过测定Zeta电位,吸光度等参数表征悬浮液稳定性,对悬浮液电泳沉积的涂层进行SEM表面形貌及粘结-拉伸结合强度的表征.结果表明:悬浮液颗粒越小,Zeta电位越高;对羟基磷灰石粉体预烧800℃,Zeta电位明显提高,且有利于涂层与基体的结合;悬浮液陈化48 h后,颗粒荷电性最佳,可得致密均匀的涂层;以乙二醇为分散溶剂可制备稳定的悬浮液,但乙醇溶剂更有利于涂层的电泳沉积;悬浮液固含量控制为20g/L时,涂层质量较好. 相似文献
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