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分别在有超声波和无超声波条件下,制备了镍镀层和电镀金刚石工具。采用显微硬度计测试了镍镀层硬度,采用热震法和锉削法测试镀层与基体的结合强度,用显微镜观察镀层金相组织,计算了工具磨削比。研究结果表明:在电镀金刚石工具制备过程中,应用超声波可以细化镀层晶粒,提高镀层硬度,增强镀层与基体的结合强度。上砂前应用超声波可提高电镀金刚石工具磨粒密度和工具的磨削比。 相似文献
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采用电刷镀技术在铸铁基体上用不同刷镀电压制备镍镀层,通过分析镍镀层截面特征、测量其显微硬度及其与基体的结合强度,研究了不同电刷镀电压下镀层组织结构和性能。结果表明,刷镀电压为5 V时,镍镀层的晶粒细密,组织均匀,硬度最高,与基体的结合强度最好,耐腐蚀性能、耐摩性能最好。 相似文献
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酸洗对钕铁硼磁体电镀镍层防护失效的影响 总被引:2,自引:0,他引:2
研究了酸洗工艺对电镀镍镀层与烧结钕铁硼基体间结合强度的影响.结果表明:经过酸洗之后,钕铁硼基体表面层变成了疏松结构,表面的显微硬度降低,镍镀层与钕铁硼基体结合强度随酸洗时间的增加而逐渐降低.通过分析剥离层的横截面发现,镀层与基体的剥离面位于钕铁硼基体内部,而不是镀层与基体的结合界面.采用垂直拉伸的剥离方法测量结合强度,表面和断面形貌通过SEM进行观察,利用维氏硬度计测量钕铁硼经过酸洗后的表面维氏硬度. 相似文献
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《中国铸造装备与技术》2016,(2)
在外加磁场的条件下对影响铜基体化学镀镍工艺的因素进行实验分析,结果表明,随着主盐浓度比的变化、施镀温度的改变以及外加磁场的不同,化学镀镍镀层的形貌、镀层与基体的结合力有所改变。其中化学镀液中主盐的浓度比对镀层与基体的结合强度影响最小,但对镀层中镍磷的含量影响较大。温度对镀层的形貌及镀层与基体的结合强度有明显影响,在40℃时结合力最好,温度越高结合力下降。随着外加磁场强度的增加镀层与基体的结合强度也随之增大。 相似文献
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耐蚀仿金镀层新工艺的研究 总被引:1,自引:0,他引:1
着重论述耐蚀仿真金镀层新工艺,研究了钢基上电镀暗镍/亮铜/亮镍/仿金镀层铜锌合金工艺和提高仿金镀层耐蚀性的后处理的钝化,浸漆工艺,通过镀层的腐蚀电位,孔隙率,耐盐雾腐蚀性能和镀液主要性能测定,表明新工艺镀涂的仿金镀层具有良好的耐蚀性。 相似文献
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复合镀覆Ti—Ni金刚石的钎焊应用 总被引:4,自引:2,他引:2
镀覆技术的研究进展表明:经过真空微蒸发镀钛、钨的金刚石单晶或聚晶,可以采用化学镀或电镀的方法在钛或钨镀层上进一步镀覆镍、钴、铬等金属,这种复合镀层与金刚石界面强力冶金结合,并且可以采用各种钎焊方法实现金刚石与多种金属基体的焊接。复合镀覆的金刚石可用于各类表镶工具的制造,获得高出刃、高磨粘结合强度,使金刚石表镶工具的使用寿命和加工效率大幅度提高。 相似文献
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高速钢W18Cr4V离子渗氮层组织对TiN膜与基体结合强度的影响 总被引:8,自引:0,他引:8
采用W18Cr4V高速钢进行离子渗氮-PECVD TiN复合处理,运用透射电子显微镜、X射线衍射仪和光学显微镜研究试样的表层组织结构。采用连续压入法研究TiN膜与基体的结合强度,结果表明,离子渗氮能够提高膜基结合强度,通过分析渗氮层与膜-基界面的组织特点,认为TiN膜在渗氮层上一些与其具有相同或相似晶体结构的氮化物上外延生长,以及强度较高的渗氮层对膜的支撑是基体渗氮提高膜-基结合强度的两大因素。 相似文献
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Seung-Yong SHIN Ji-Hyun LEE Hai-Woong PARK 《中国有色金属学会会刊》2009,19(4):961-964
The electrical properties of solder contact layers between Cu-Ni shunt metal and tube type Bi2212 superconductor that is applied in superconducting fault current limiter were studied. The contact properties of the solders are improved not only by Ag precoating layers, but also by the pre-sprayed Ag layer and subsequent Ag precoating layers. The annealed Ag sprayed layers onto Bi2212 superconductor prior to Ag electroplating work as protecting layers for the superconductor from plating solutions. The contact angle of the electroplated Ag layer is 42.91° and decreases to 15.25° and 5.88° with Ag sprayed layer and additional Ag electroplated layers. The Ag sprayed layer with suitable annealing prior to Ag electroplating improves contact strength of the Ag electroplated layer by about 12% due to denser microstructure of the Ag electroplated layers. 相似文献
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Wolfgang Paatsch 《工业材料与腐蚀》1988,39(4):167-172
Avoidance of hydrogen embrittlement of high strength steels during electroplating processes by thermal alloying Low alloyed high strength steels are often electroplated by metal layers protecting against corrosion. For ultra high strength, quenched and tempered steels with yield strengths > 1000 Nmm?2 embrittlement by hydrogen being envolved during the electrochemical pretreatment as well as metal deposition has to be avoided. More over the corrosion protecting layers should form a diffusion barrier for hydrogen which can be formed during corrosion processes under special circumstances. In this paper two problem solutions including thermal alloying processes will be discussed. Plating the steel substrate with a nickel layer subsequently annealed at a temperature above 800°C in an inert gas atmosphere an austenitic iron-nickel-alloy at the boundary is formed, being a high efficient diffusion barrier for hydrogen. Further zinc plating is improving the corrosion resistance avoiding at the same time pitting corrosion problems. Plating the steel substrate with a copper and a following nickel layer on top and annealing it at the temperature of 800°C a highly corrosion resistant copper-nickel-alloy is formed showing excellent barrier behaviour for hydrogen diffusion. In both cases hydrogen being formed during the plating process itself and penetrating into the base metal does not lead to embrittlement as it is effusing during the annealing procedure. 相似文献
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在波导器件中,铝合金壳体较差的润湿性制约了其与微带电路板之间大面积、可靠低温钎焊连接. 通过电弧喷涂技术在5A06铝合金表面制备了厚度约为80 μm的Ag-15%Ni(质量分数)单一涂层和Ni-5%Al/Ag-15%Ni(质量分数)复合涂层,以提升Sn-Pb钎料在其表面的润湿性. 对比研究了两种涂层的显微结构、涂层界面结合性能、低温钎焊行为及钎焊接头剪切失效机制. 结果表明,涂层与铝合金基板间形成了良好的界面结合,并且两种涂层均具有较好的低温焊接性. 其中,Ag-15%Ni单一涂层与铝合金基板的结合强度为40 MPa,喷涂后铝合金基板与T2紫铜形成的钎焊接头抗剪强度为26 MPa. 相较而言,Ni-5%Al /Ag-15%Ni复合涂层展现出更佳的涂层结合强度(42 MPa)和钎焊接头抗剪强度(31 MPa). 相似文献
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The role of the electroplated nickel layer on hydrogen permeation through AISI 4340 steel was investigated by a electrochemical
hydrogen permeation test. The permeation test, composed of three steps, was conducted to measure the hydrogen diffusivity
and surface hydrogen concentration. A constant current of 20 mAcm-2 and a constant potential of -100 mV vs. Ag/AgCl electrode were applied to the hydrogen entry and exit cells, respectively.
The thickness of the electroplated nickel layer on AISI 4340 steel increased in a linear fashion with an increase in electroplating
time. The nickel coated layer contributed to a decrease in the hydrogen permeability of nickel coated AISI 4340 steel specimens.
This is due to the fact that the surface hydrogen concentration and hydrogen diffusivity in nickel coated layer were lower
than those of AISI 4340 steel substrate. Especially, low hydrogen diffusivity decreased significantly with hydrogen permeability.
The critical effective hydrogen diffusivity for barrier of nickel electroplated AISI 4340 steel specimens was higher than
the hydrogen diffusivity of AISI 4340 steel specimen. It is proposed then that the thin nickel layer on AISI 4340 steel acts
as a barrier for hydrogen permeation through AISI 4340 steel. 相似文献
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选取Ti箔作为钨与铜合金(CuCrZr)连接的中间层,考察了连接温度对扩散连接接头的显微结构和强度性能的影响。结果表明:扩散层中脆性金属间化合物对接头强度有重要影响,当连接温度为1030℃时,Ti与Cu发生共晶反应全部转化为液相并且大部分被挤出连接区域,少量残留的金属间化合物促进接头强度提高,剪切强度甚至超过W母材。 相似文献
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目的 研究不同厚度的ZEP-520电子束光刻胶胶层的韧性以及其与衬底间的结合强度等力学性能,为解决光刻胶层在使用过程中的开裂及脱落问题提供实验支持.方法 利用纳米划痕技术对不同厚度下的ZEP-520电子束光刻胶进行了划痕测试,分析了光刻胶开始破损和完全脱粘时的临界载荷,研究了胶层厚度与光刻胶韧性的定量关系,并以光刻胶胶层与硅基底的结合能评价了其结合强度.此外,在厚度为587 nm的光刻胶胶层上,利用电子束曝光技术成功制备了频率为10000线/mm的高质量正交光栅,采用几何相位分析法对栅格间距误差进行了定量表征.结果 ZEP-520光刻胶胶层的韧性、结合力以及结合能均随胶层厚度的增加而增加,结合能在光刻胶胶层厚度大于529 nm时,趋于定值0.17 J/m2.利用几何相位分析法测得所制备的光栅间距误差在1.3%以内,并且未存在开裂以及脱粘等现象.结论 在ZEP-520电子束光刻胶胶层微纳米成形过程中,适当增加光刻胶胶层厚度可以有效增强胶层韧性和其与衬底之间的结合力,缓解光刻胶胶层在使用过程中出现裂纹与脱落的现象. 相似文献