Ni—Fe—P／Al2O3复合镀层的硬度和耐磨性

对不同工艺条件下获得的Ｎｉ－Ｆｅ－Ｐ／Ａｌ２Ｏ３复合镀层的显微硬度及其耐磨性进行了研究。结果表明,复合层的显微硬度和耐磨性随Ａｌ２Ｏ３复合量,镀液中ＮａＨ２ＰＯ２·Ｈ２Ｏ浓度,电流密度以及施镀温度的改变而变化。在改变工艺参数的过程中,复合镀层显微硬度比Ｎｉ－Ｆｅ－Ｐ电沉积层平均高约Ｈｖ１００￣１６０。     

( Ni-P)-Al2O3纳米微粒复合镀层硬度和耐磨性测试

为了改进钢材表面性能,采用复合化学镀技术制备( Ni-P) -Al2O3纳米微粒复合镀层,由于纳米微粒独特的物理化学特性致使使得到的复合镀层具有多种优良性能.通过Ni-P合金镀层、(Ni-P) -Al2O3纳米微粒复合镀层和热处理后的(Ni-P) -Al2O3纳米微粒复合镀层硬度和耐磨性能测试,得出(Ni-P)-Al2...     

Ni-Al2O3复合镀层的微观形貌与其耐磨耐蚀性能

测试了Ni基超细Al2O3粉复合镀层的耐磨性,测定了该镀层的孔隙率和耐蚀性,用电子显微镜观察复合镀层的微观形貌。结果表明,随镀液温度升高,复合镀层晶粒细化;随电流密度的增加,复合镀层晶粒变粗。当超细氧化铝粉体全部被镍包覆且复合镀层的晶粒细致时,耐磨性最好。当复合镀层的结晶较细致或氧化铝粉的含量较高时,其孔隙率较低。在较高的镀液温度(65℃)和较高的电流密度(3.5~4 A/dm2)时,镀层的耐盐雾性能较好。     

AI2O3溶胶的体积分数对Zn-Ni-AI2O3复合镀层性能的影响

向Zn-Ni合金镀液中加入AI2O3溶胶,获得了Zn-Ni-AI2O3复合镀层。研究了A12O3溶胶的体积分数对镀层的相结构、表面形貌、横截面形貌、显微硬度、耐磨性及耐蚀性的影响。结果表明:当A12O3溶胶的体积分数低于6 mL/L时,不会对镀层的相结构产生影响。但当A12O3溶胶的体积分数较高时,会改变镀层的相结构,并影响镀层的致密性。当AI2O3溶胶的体积分数为6 mL/L时,镀层的耐磨性和耐蚀性均最佳。     

热处理对（Ni—P）—SiC复合镀层耐磨性的影响

研究了热处理工艺对沉积在钢铁上的(Ni-P)-SiC复合镀层的影响.结果表明,镀层经470℃×2h热处理后,其硬度和结合力达到良好的配合,耐磨性最佳.     

Ni-P-纳米Al2O3复合镀层耐磨性能研究

本文通过在Ni-P合金化学镀液中加入纳米α-Al2O3颗粒,获得Ni–P–纳米Al2O3复合镀层。采用SEM对Ni–P–Al2O3复合镀层的表面形貌进行分析;采用EDX对复合镀层中的元素进行分析;用显微硬度计测量了不同Al2O3质量分数下镀层的硬度值;通过MM-W1立式万能摩擦磨损试验机对复合镀层的磨损性能进行了评价,并分析了复合镀层的磨损机理。结果表明:纳米Al2O3的加入可以增加镀层的硬度,并能有效地降低摩擦副之间的犁沟效应及摩擦表面发生粘着的面积,从而减少镀层的磨损。     

Al2O3-Ni-P复合刷镀工艺的研究

研究了电刷镀Al2O3-Ni-P工艺,考察了相关因素对复合刷镀层中Al2O3微粒的含量和镀层沉积速度的影响,通过金相显微镜观察了复合刷镀层的表面形貌.结果表明:使用合适的工艺,可以获得良好的Al2O3-Ni-P复合刷镀层.     

摩擦喷射电沉积制备Ni-Al2O3纳米复合镀层

采用摩擦喷射电沉积工艺制备了N i-A l2O3纳米复合镀层。研究了电压、镀液中纳米颗粒含量、镀液喷射速度、镀笔相对运动速度等工艺参数对镀层沉积速度以及镀层中纳米颗粒含量的影响。结果表明,电压对镀层沉积速度影响较大,电压、镀液中纳米颗粒含量对复合含量的影响较大。扫描电镜及能谱测试显示,该纳米复合镀层表面较为平整、致密,纳米颗粒在镀层中呈均匀弥散分布,含量在2%~5%。     

化学复合镀Ni-P-Cr_2O_3工艺及镀层性能的研究

研究了Ni P Cr2 O3 化学复合镀工艺 ,以及热处理对镀层硬度、耐磨性的影响 ,并与Ni P镀层作了对比。结果表明 ,通过制定合理的镀制工艺和控制镀液中Cr2 O3 固体颗粒的添加量 ,可提高镀速 ,获得Cr2 O3 颗粒含量适宜的复合镀层。另外 ,采用正确的热处理工艺 ,可使镀层的硬度、耐磨性显著改善     

纳米复合镀层中Al2O3的测定

在六次甲基四胺和表面活性剂CPB介质中,Al3 与铬天青-S反应生成稳定配位化合物,体系的最佳吸收波长为630nm.研究表面活性剂、酸度、显色剂、显色时间及共存离子对测定结果的影响.结果表明:铝的质量浓度在0～12.0 mg/L范围内遵守比尔定律,表观摩尔吸光系数为4.04×104.方法简便、准确,用于镍基纳米复合镀层中Al2O3共析量的测定.     

Adhesion enhancement in Fe-Al2O3 and Cu-Al2O3 metal-ceramic systems induced by ion beam mixing

The ion beam mixing technique is well adapted to treat metal-ceramic interfaces under low temperature and non-equilibrium conditions. Using this technique, we have mixed Cu-Al₂O₃ and Fe-Al₂O₁ interfaces in order to improve the adhesion. Cu and Fe metallic layers having thicknesses of less than ~ 100 nm were deposited on optical grade polished surfaces of sapphire substrates. Ion beam mixing experiments were performed at room temperature with xenon, krypton, argon, and neon ions of various energies and fluences ranging from 10¹⁵ to 4 x 10¹⁶ ions per cm². A linear increase of adhesion with ion mixing was observed for all the ions and systems studied. A strong dependence of adhesion on the energy transfer, controlled by the nature and energy of the incident ions, was observed, allowing us to optimize the adhesion enhancement in the particular case of the Nebombarded Fe-Al₂O₃ interface. The microstructural and chemical effects induced at the interface during the ballistic phase of the mixing process responsible for the adhesion enhancement were characterized by high resolution transmission electron microscopy and associated measurements using X-ray photoelectron (XPS) and Auger electron spectroscopy (AES) as well as conversion electron Mössbauer spectrometry (CEMS). The presence of a non-equilibrium phase formed at the interface in a thin layer (3-5 nm), containing the atoms displaced in the nuclear collision cascades during the short-time ballistic phase of the mixing process, was detected and is responsible for the metal-ceramic adherence.     

Er2O3掺入对氧化铝复合陶瓷的耐磨性和微观结构影响

以工业Al2 O3为主要原料,CaO-MgO-SiO2作为烧结助剂的体系中,研究了Er2 O3的添加对高铝瓷的耐磨性的影响.结果表明:过量添加Er2 O3明显提高了陶瓷样品的烧结温度,陶瓷的耐磨性能也被恶化.而微量添加Er2O3对陶瓷的烧结温度影响不大,且耐磨性能提高了约22％.     

化学复合镀的研究现状及镀层的应用

化学复合镀层因复合粒子的性能特点而广泛应用本文就国内外化学复合镀的研究现状和发展趋势进行了综述具体从硬度、耐磨性、自润滑性方面对各种Ni-P基、Ni-B基化学复合镀的工艺研究及镀层结构与性能特点进行了阐述,并认为目前关于化学复合镀的研究仍然集中在耐磨和自润滑镀层方面对不同化学复合镀层的应用做了总结,并对其提出了展望。     

超声波作用下纳米Al2O3粉体化学镀Cu的研究

在超声波作用下,对100nm左右的Al2O3粉体进行化学镀铜,从化学镀铜热力学和动力学两方面对其机理进行探讨。同时借助X射线衍射判断其成分组成,用SEM观察镀覆结果,结合EDAX光电子能谱仪对其进行表面元素分析。结果表明：引入超声波可以实现纳米Al2O3粉体的化学镀铜,以EDTA-2Na为配位剂,并加入亚铁氰化钾为稳定剂,可以有效地消除或减少复合粉体中的Cu2O,可以一次镀覆得到铜含量为5％～90％的Cu—Al2O3复合粉体。     

Effect of Tm2O3 on the properties of corundum-mullite composite ceramics for solar heat transmission pipelines

Corundum-mullite composite ceramics appropriate for application in solar heat transmission pipelines were fabricated by the addition of Tm₂O₃ and sintered at atmospheric pressure. The results demonstrated that with the introduction of Tm₂O₃ (1–7 wt.%), the physical and mechanical properties, corrosion resistance, and thermal shock resistance of the composite ceramics were significantly enhanced. The sintered sample AT5 (with 5 wt.% of Tm₂O₃ added) showed the best overall performance at 1550°C. The residual bending strength remained higher than 186 MPa after corrosion with 20 wt.% H₂SO₄ solution and 10 wt.% sodium hydroxide solution. The reaction of Tm₂O₃ with the Al₂O₃–SiO₂ system produced the Tm₂O₃–Al₂O₃–SiO₂ liquid phase. This liquid phase eliminated the pores through viscous flow, resulting in a dense microstructure. Furthermore, more mullite and dithulium disilicate were generated after thermal shock cycles, and their inhibition of crack deflection and extension allowed the composite ceramics to achieve excellent thermal shock resistance (residual bending strength as high as 199 MPa). The prepared corundum-mullite composite ceramics have a good potential for application in solar heat transmission pipelines.     

Fe-Al金属间化合物/Al2O3陶瓷复合材料研究

文章介绍了一种新型的Fe-Al金属间化合物/氧化铝陶瓷复合材料.该材料的抗弯强度和断裂韧性随着Fe-Al金属间化合物含量的增加而提高,但硬度降低.     

Ni-Al2O3复合镀层的腐蚀摩擦学性能研究

用电镀方法制得Ni-Al2O3复合镀层,研究电镀Ni-Al2O3复合镀层的结构以及其硬度、耐磨性、抗腐蚀性与电镀电流密度的关系。结果表明:复合镀层的显微硬度比纯镍镀层硬度成倍提高,复合镀层耐磨性比镍镀层提高20%以上;抗腐蚀性提高70%以上。X射线衍射结果显示,复合镀层由Ni及非晶Al2O3组成,Ni相为面心立方晶体结构,晶格常数为0.353nm,小于纯镍镀层,晶粒尺寸为23.8nm,大于纯镍镀层。