镍钴离子浓度比对化学镀Co-Ni-P合金组织结构和性能的影响

化学镀ＣｏＮｉＰ合金层镀态下为非晶态结构，以层片状沉积，表面有胞状结构。［Ｎｉ２＋］／［Ｃｏ２＋］的比值越大，胞块越大，晶化倾向越大，镀层显微硬度越高，矫顽力越小，矩形比越大。其易磁化方向与膜面垂直。随加热温度升高，化学镀ＣｏＮｉＰ合金发生了晶化转变，析出了第二相，显微硬度在４００℃／１ｈ热处理后达到最高值。     

热处理对超临界电沉积Co-Ni-P合金薄膜的摩擦学与电化学腐蚀性能影响研究*

采用超临界二氧化碳（S-CO₂）辅助电沉积及后续热处理（200～600℃）制备钴-镍-磷（Co-Ni-P）三元合金涂层,热处理时间为1 h。研究不同热处理温度对超临界电沉积制备的Co-Ni-P三元合金涂层的微观形貌、相结构、硬度、摩擦学性能和电化学腐蚀性能的影响。结果显示:超临界CO₂电沉积制备的Co-Ni-P三元合金呈现非晶结构,但经过400℃热处理后由非晶结构转变为晶体结构;Co-Ni-P涂层的硬度随着热处理温度增加先升高后降低,当热处理温度为400℃时,表面硬度最高,约为780 HV。摩擦学和电化学腐蚀性能测试显示:热处理对Co-Ni-P薄膜的平均摩擦因数影响较小,处理前后合金涂层的平均摩擦因数均为0.12左右;但热处理显著影响Co-Ni-P合金薄膜的耐磨性能和电化学腐蚀性能,其磨损率和腐蚀速率随着热处理温度升高先减少后增加;当热处理温度在300和400℃时,Co-Ni-P合金分别呈现最低的磨损率和最好的耐腐蚀性能。     

超声波化学镀Co-Ni-P工艺

Co-Ni-P化学镀层具有很多优点,在超声波辅助下化学镀层更光亮、细腻。在超声波辅助下在铝黄铜表面化学镀Co-Ni-P合金镀层,研究了镀液主盐浓度比、还原剂浓度、配位剂浓度、缓冲剂浓度、温度、pH值对沉积速率的影响,确定了超声波辅助下获得最佳沉积速率的化学镀Co-Ni-P工艺。结果表明:最佳工艺为11.0g/LNiCl2.6H2O,5.5g/LCoCl2.6H2O,17g/LNaH2PO2.H2O,50g/LNa3C6H5O7.2H2O,48g/LNH4Cl,温度75℃,pH值9.0;超声波化学镀层为非晶态结构,分布更均匀,表面更光亮。     

十六烷基三甲基溴化铵对化学镀Co-Ni-P的影响

通过正交试验得到化学镀Co-Ni-P的优化基础配方(g.L-1)和施镀条件:CoSO4.7H2O为16、NiSO4.6H2O为9、NaH2PO2.H2O为30、Na3C6H5O7.2H2O为60、(NH4)2SO4为70,于pH=10、80℃施镀1 h;研究了阳离子表面活性剂十六烷基三甲基溴化铵对Co-Ni-P镀层成分以及镀层与基体结合力的影响。实验结果表明,在优化的基础配方中加入30 mg.L-1的十六烷基三甲基溴化铵,镀液稳定性好,沉积速率加快,镀层表面光亮,镀层与基体的结合力增强,镀层中钴含量增加,镍、磷含量降低,镀层的性能得到了很大的改善。     

粉煤灰空心微珠的Co-Ni-P化学镀及镀层的吸波性能

为了实现吸波材料的薄型化及轻量化,采用化学镀工艺对粉煤灰空心微珠(5μm级)进行表面电磁改性,制备出"核-壳"结构新型轻质复合粉体吸波材料,探讨了Co-Ni-P化学镀工艺参数对吸波性能的影响.借助SEM,EDS和微波矢量网络分析仪研究了施镀工艺参数对镀层形貌、成分与吸波性能的影响.结果表明,空心微珠表面镀层由粒径0.5...     

Electrodeposition of hard magnetic films and microstructures

Electrochemical deposition of materials with hard magnetic properties in the as-deposited state is essential for the efficient integration of micro-magnetic components into MEMS devices. Here we discuss the growth process and the microstructure-magnetic properties correlation for two Co-rich alloys, Co-Ni-P and Co-Pt. Under suitable synthesis conditions, these materials exhibit perpendicular anisotropy and hard magnetic properties in the as-deposited state; in addition, such properties are maintained up to several micrometer film thickness through close control of the film microstructure. In the case of Co-Ni-P films we achieved a saturation magnetization of 1.21 T (963 emu/cm³), perpendicular coercivity up to 188 kA/m (2.36 kOe) at a thickness of 10 μm, and energy products up to 4.2 kJ/m³. Co-rich Co-Pt films were grown on several substrates - Cr, Cu(0 0 1), Cu(1 1 1), and Ru(0 0 0 1) - in order to control magnetic anisotropy and achieve optimum hard magnetic properties. Cu(1 1 1) contributes to stabilize the hexagonal hcp phase at high current density yielding excellent hard magnetic properties, although only in films thicker than 100 nm; saturation magnetization in these films was about 1.04 T (828 emu/cm³). Perpendicular coercivities up to 485.6 kA/m (6.1 kOe) were obtained in 1 μm thick film deposited at 50 mA/cm². Ru(0 0 0 1) seed layers provide an appropriate interface structure to further facilitate the epitaxial growth of hcp films, yielding hard magnetic properties and perpendicular coercivity with a squareness ∼1 in films as thin as 10 nm. The hard magnetic properties were only marginally compromised at large film thickness. Deposition at higher current density (50 mA/cm²) favored markedly improved hard magnetic properties. The Co-Pt films on Ru exhibited perpendicular anisotropy with anisotropy constant up to 1.2 MJ/m³. The electrodeposition process was further extended to fill lithographically patterned hole arrays (850 nm diameter, center-to-center distance 2550 nm and about 700 nm thick resist), yielding arrays of micron-sized hard magnetic cylinders with perpendicular coercivity of 361 kA/m (4.54 kOe) and high squareness.     

化学镀Ni-P/Co-Ni-P(La)复合阴极的性能研究

化学镀Ni-P/Co-Ni-P阴极具有很好的电催化性能和抗蚀性能,但在长期电位稳定性方面和抗反电流能力方面不能令人满意。在外层引入稀土元素La后,由于稀土元素特殊的外层电子结构,促进了它的抗氧化性能。化学镀Ni-P/Co-Ni-P(La)复合阴极,分别经120℃或350℃热处理,相对于同样条件下的化学镀Ni-P/Co-Ni-P阴极,长期电解的稳定电位下降60mV和10mV,在抗反电流实验中平台电位也下降了80mV和35mV,表现出良好的电位稳定性和抗反电流能力。     

化学镀Co-Ni-P薄膜的组织结构和生长机理研究

利用Ｈ－８００透射电镜和Ｄｍａｘ／ｒｂ旋转阳极Ｘ－射线衍射仪分析了化学镀Ｃｏ－Ｎｉ－Ｐ三元合金薄膜的组织结构,并采用原子力显微镜观察了镀层的表面生长形貌,探讨了其生长机理。结果表明,随镀液中［Ｃｏ２＋］／［Ｃｏ２＋］＋［Ｎｉ２＋］的增大,镀层中Ｃｏ含量相应增加,Ｎｉ和Ｐ含量则下降。当Ｃｏ－Ｎｉ－Ｐ镀层中Ｐ含量小于５．０％时,镀层为晶态,且晶粒随着镀层的增厚而长大。随Ｎｉ和Ｐ含量的增高,镀层向非晶结构过渡;当Ｐ含量大于６．５％时,镀层经很薄的微晶过渡区后很快以非晶结构生长;当镀层含磷量处于５．０％～６．５％过渡区时,初期镀层为１２０ｎｍ左右的微晶,厚度增加时,晶粒尺寸迅速减小。     

铈对化学镀Co-Ni-P合金薄膜结构及磁性的影响

利用等离子发射光谱仪、电子能谱仪、X-射线衍射仪和振动样品磁强计等分析了Ce对化学镀Co-Ni-P合金层成分、结构和磁性能的影响.结果表明:随镀液中ρ(Ce)的增加,化学镀Co-Ni-P镀层中的Ce、Co和Ni含量有所增加,P的含量则相应降低;镀层由非晶态Co-Ni-P合金镀层转变成了具有微晶、晶态结构的Co-Ni-P-Ce合金镀层.稀土Ce的加入提高了镀层的饱和磁化强度和矫顽力,降低了剩余磁化强度.