电沉积Ni—P,Ni—P—Si3N4非晶态合金及其结构,性能研究

研究了Ｎｉ－Ｐ、Ｎｉ－Ｐ－Ｓｉ３Ｎ４非晶态合金薄膜的是沉积工艺，通过ＳＥＭ－ＥＤＳ，ＸＲＤ，ＥＭＰＡ等微观分析方法，提出了获取８￣１４ｗｔ％Ｎｉ－Ｐ和Ｎｉ－Ｐ－Ｓｉ３Ｎ非晶合金镀层的镀液组成和电沉积参数。实验表明，Ｎｉ－Ｐ非晶态合金镀层在碱液中具有优越的耐蚀性能，在含Ｃｌ＾－１的中性盐液中有良好的耐蚀性，且不产生点蚀；Ｎｉ－Ｐ－Ｓｉ３Ｎ４非晶合金镀层，经晶化处理后，耐蚀性能提高，且与基材呈冶金结合     

Fe（OH）3中微量金属离子对水热合成α—Fe2O3粒径的影响

本文研究了某些金属离子（Ａｌ＾３＋、Ｍｎ＾２＋、Ｚｎ＾２＋、Ｃｒ＾２＋、Ｎｉ＾２＋、Ｃｏ＾２＋）Ｆｅ（ＯＨ）３凝胶经水热法合成的α－Ｆｅ２Ｏ３微粉颗粒大小的影响。研究结果出现，随着金属离子的浓度在一定范围内（０．０１０－０．０５０ｍｏｌ·Ｌ＾－１）的增加，α－Ｆｅ２Ｏ３颗粒有减小的趋势。其中加入Ｃｏ＾２＋（０．０５０ｍｏｌ·Ｌ＾－１）、Ｍｎ＾２＋（０．１００ｍｏｌ·Ｌ＾－１）可以得到粒径为７５ｎｍ     

镍合金化学镀层的阳极行为及局部腐蚀

利用电化学测试及Ｘ射线光电显微（ＸＰＳ）、扫描电镜（ＳＥＭ）等方法，研究了镍合金化学镀层在酸性介质中的阳极行为局部腐蚀，结果表明，由于Ｎｉ－Ｐ合金中磷的不均匀分布及胞界等的存在，在Ｃｌ＾－的作用下，Ｎｉ－Ｐ合金发生孔蚀。Ｎｉ－Ｐ合金表面膜由Ｎｉ（ＯＨ）２及Ｎｉ３（ＰＯ４）２组成，在开路及电位较低时，以Ｎｉ（ＯＨ）２为主，在电位较高时，以Ｎｉ３（ＰＯ４）２为主。阳极极化过程中，由于表面膜组成的改变导     

镍—钨—磷合金镀层在硫酸介质中的耐蚀性

研究了自催化镀Ｎｉ－Ｗ－Ｐ合金镀层在Ｈ２ＳＯ４介质中的耐蚀性，结果表明，在１０％－２０％（ｗｔ）Ｈ２ＳＯ４介质中，Ｎｉ－Ｗ－Ｐ合金镀层有极好的耐蚀性，这是由于一定组成的Ｎｉ－Ｗ－Ｐ合金镀层具有非晶态结构及表面极易形成致密的钝化膜所致。     

氧化钛薄膜电致变色性质研究

通过在循环伏安过程中对透过率的实时测定,研究了由水相溶胶－凝途径制得的ＴｉＯ２薄膜的电致变致变色特性,在Ｉｍｏｌ／ｄｍ＾３ＨＣｌ溶液中,经１５０℃和３５０℃处理的ＴｉＯ２薄膜在６３０ｍｍ处的着色效率分别为８．８、４．９ｃｍ＾２／Ｃ, 循环稳定性都较差,在１ｍｏｌ／ｄｍ＾３ＬｉＣｌＯ４的碳酸丙烯酯溶液中,经４５０℃处理的Ｔdisplay status     

CO2饱和高温弱酸性介质中Ni-Cu-P合金、纯Ni和A3钢的电化学行为

用线性极化法,极化曲线法和失重法研究了化学镀Ｎｉ－Ｃｕ－Ｐ非晶态合金,纯Ｎｉ和Ａ３钢于１４０℃,ｐＨ值５．０、ＣＯ２饱和的２Ｗ（ｗｔ）ＮａＳＯ４溶液中的腐蚀电化学行为,结果表明,在该介质条件下,Ｎｉ－Ｃｕ－Ｐ合金、纯Ｎｉ和Ａ３钢的耐蚀性依次减弱,比值为８１．２：２３．９：１．０。Ｎｉ－Ｃｕ－Ｐ合金于２５０￣５５０ｍＶ（ｖｓ ＯＰ）区间发生钝化;纯Ｎｉ在５０￣１５０ｍＶ和高于４００ｍＶ（ｖｓＯＰ）区     

电镀规范对Fe—Ni—P合金硬度和耐磨性的影响

研究了不同电镀规范的Ｆｅ－Ｎｉ－Ｐ合金层显微硬度和摩擦学性能。镀液中Ｆｅ／（Ｆｅ＋Ｎｉ）浓度比增大或电流密度增加，镀层的硬度上，耐磨提高；槽液的ＰＨ值或温度增大，镀层的显微硬度下降，耐磨性降低。镀液ＮａＨ２ＰＯ２．Ｈ２Ｏ浓度为５ｇ／Ｌ时，镀层硬度和磨性最高。宜选用的工艺参数为ＰＨ值１．０－１．２，温度６０－７０℃，电流密度１０－２０Ａ／ｄｍ＾２。Ｆｅ－Ｎｉ－Ｐ非晶合金的耐磨性比Ｎｉ－Ｐ非昌合金高２     

Al2O3-Na2O-CaO-SrO系统富Al2O3区域固态反应的研究

用理学Ｘ射线衍射仪、ＴＧ－ＤＴＡ、ＩＲ－４４０ 红外光谱研究了Ａｌ２Ｏ３－Ｎａ２ Ｏ－ＣａＯ－ＳｒＯ系统富Ａｌ２Ｏ３ 区域固态反应。实验结果表明,煅烧过程固态反应的最终物相组成为Ｎａ２Ｏ·１１Ａｌ２Ｏ３,ＣａＯ·６Ａｌ２Ｏ３ ,ＳｒＯ·６Ａｌ２Ｏ３ 与α－Ａｌ２Ｏ３ 共存     

高电流密度下Zn—Ni合金电镀工艺

在１０～３０Ａ／ｄｍ＾２电流密度范围内对硫酸盐体系锌－镍合金电沉积的规律进行了研究，确定了准动态锌－镍合金电镀工艺。锌－镍合金电沉积是异常共沉积。［ＮｉＳＯ４·６Ｈ２Ｏ］／［ＮｉＳＯ４·６Ｈ２Ｏ＋ＺｎＳＯ４·７Ｈ２Ｏ］浓度比增加使镀层中镍含量增大；电流密度增加使镀层中镍含量下降。准动态锌－镍合金电镀工艺阴极电流效率为９５％，电沉积速度为３８ｇ／ｍ＾２·ｍｉｎ；镀得的镀层外观为青白色带有金属光泽的良     

W,P对Ni基非晶镀层耐蚀性能的影响

电沉积Ｎｉ－Ｐ，Ｎｉ－Ｗ和Ｎｉ－Ｗ－Ｐ非晶态合金镀层的阳极化曲线表明，添加类金属Ｐ使镀层的腐蚀电位向正移动，添加高熔点金属Ｗ使维钝电镀密度降低，此外，对Ｎｉ－Ｗ和Ｎｉ－Ｗ－Ｐ合金镀层进行印化处理，可显著提高镀层在ＮａＣｌ溶液中的耐腐蚀性能。     

非晶态Ni－W合金电镀及其耐蚀性研究

本文研究了Ｎｉ－Ｗ非晶态合金电镀共沉积的规律及其耐蚀性。结果表明，镀膜中钨含量达到４３．３ｗｔ％以上时，形成非晶态结构，且该镀膜可在较宽的电势范围内形成钝化膜，具有较强的耐蚀性     

Ti基金属玻璃复合材料的腐蚀行为

采用水冷铜坩埚悬浮熔炼-铜模吸铸法制备了直径为3mm的(Ti0.5Ni0.5)80Cu20金属玻璃复合材料试样,对合金的组织结构进行表征,用电化学工作站三电极体系测试了不同腐蚀介质中的动电位极化曲线,并分析表征电化学腐蚀后的形貌和腐蚀产物。结果表明:合金组织由非晶基体+形状记忆晶体相组成,在铸造过程的温度梯度下呈现梯度组织,边缘为快冷形成的无序密堆非晶结构,心部主要析出相为过冷奥氏体相。在人工海水和模拟人体的PBS溶液中,合金均表现出良好的耐蚀性。与晶态TC4合金相比,自腐蚀电位高,腐蚀的热力学倾向小;自腐蚀电流密度低,极化电阻高,腐蚀的动力学速率低。合金在PBS溶液中由于介质中活性阴离子浓度低,比在人工海水中表现出更优异的抗蚀性。在腐蚀形貌中未发现点蚀坑,边缘区的氧化膜较心部区域更为致密均匀。     

电沉积镍基合金及其耐磨耐蚀性能研究

采用电沉积方法制备出Ｎｉ－Ｃｏ晶态合金及Ｎｉ－Ｃｏ－Ｐ晶态、非晶态合金,并对它们的硬度及耐磨耐蚀性能进行了调查,指出非晶态Ｎｉ－Ｃｏ－Ｐ合金是一种优良的耐磨耐蚀材料。     

A study of corrosion performance of electroless Ni–P and Ni–W–P coatings on AZ91D magnesium alloy

The autocatalytic nature of the electroless nickel‐based alloy coating process will inevitably produce H₂ bubbles which may be left in electroless nickel‐based alloy coating. If the H₂ cannot be removed and left in the coating, it can lead to its poor corrosion resistance due to hydrogen cracks. So, the post treatment is an essential step for electroless deposition process. In this paper, electroless Ni–P and Ni–W–P coatings with chromium‐free pretreatment and dehydrogenation post treatment have been successfully prepared on AZ91D magnesium alloy, and the corrosion behaviors of the two kind coating samples in NaCl solution, HCl solution, and H₂SO₄ solution have been investigated. Both the polarization test and immersion tests show that the electroless Ni–W–P coating has better corrosion resistance than that of electroless Ni–P coating.     

Ni–P amorphous phases obtained by Nd–YAG pulsed laser alloying of deposited Ni–P coating with aluminum

Ni–P electroless deposited coating with crystalline morphology was prepared on aluminum substrate. A Nd–YAG pulsed laser was used to alloy the materials at the condition of power density 5.36 × 10⁹ W/m² and scanning speed 3.0 mm/s. In the laser alloyed layer, Ni–P amorphous phases were found by means of TEM. Electron diffraction patterns and X-ray diffraction results showed that these Ni–P amorphous phases were decomposed as Ni and Ni₃P equilibrium phases when tempered at temperature over 300 °C.     

In vitro corrosion and cytotoxicity on microcrystalline, nanocrystalline and amorphous NiTi alloy fabricated by high pressure torsion

Bulk nanocrystalline and amorphous Ni50.2Ti49.8 alloy samples were successfully prepared from commercial microcrystalline Ni50.2Ti49.8 alloy discs by high pressure torsion (HPT) technique. Then their corrosion resistance, surface wettability and cytotoxicity were further studied from the viewpoint of biomaterials. In both Hank's solution and artificial saliva, bulk nanocrystalline and amorphous Ni50.2Ti49.8 alloys showed significantly higher pitting corrosion potentials than that of microcrystalline Ni50.2Ti49.8 alloy. Meanwhile, the amount of Ni ion release after immersion in Hank's solution was minor, far below the threatening threshold of daily diet. Murine fibroblast and osteoblast cell lines were indirectly co-cultured with experimental sample extracts, indicating no cytotoxicity. Amongst all samples, the nanocrystalline Ni50.2Ti49.8 shows promising as best biomaterial candidate for its good combination of mechanical property, corrosion resistance and cytocompatibility.     

热处理对化学沉积Ni-P、Ni-Co-P合金组织及耐蚀性能的影响

研究了热处理对化学沉积Ｎｉ－Ｐ、Ｎｉ－Ｃｏ－Ｐ合金镀层的组织结构、显微硬度、常温静态腐蚀性能和热溶液腐蚀性能的影响。结果表明，Ｎｉ－Ｃｏ－Ｐ合金镀层的显微硬度高于Ｎｉ－Ｐ合金镀层；Ｎｉ－Ｃｏ－Ｐ合金镀层的耐热溶液腐蚀性能及４００℃热处理后的常温静态腐蚀性能均优于Ｎｉ－Ｐ合金。     

Ti-Zr-Be-Cu-Co块体非晶合金在NaCl溶液中的冲刷腐蚀行为

为评价Ti基块体非晶合金的耐蚀性,以期今后在工业生产中的应用,采用失重法研究了Ti35Zr30Be2 4Cu7.5Co3.5块体非晶合金及其对应晶体成分在质量分数6%Na Cl溶液中0.2、0.4、0.6 m/s流速下的冲刷腐蚀行为.利用X射线分析(XRD)、扫描电镜(SEM)研究了Ti35Zr30Be2 4Cu7.5Co3.5块体非晶合金及其对应晶体成分的相结构、微观腐蚀形貌,并利用电化学极化试验测试2种合金冲刷腐蚀后的耐蚀性.结果表明:随着流速的增加,2种合金的腐蚀速度均升高,其中非晶合金出现最大腐蚀速度峰值的时间由无冲刷状态的32 h缩短到流速为0.6 m/s下的10 h,Ti35Zr30Be2 4Cu7.5Co3.5块体非晶合金腐蚀速度较对应晶体成分小;Ti35Zr30Be2 4Cu7.5Co3.5块体非晶合金较对应晶体成分在质量分数6%NaCl溶液中具有更好的耐蚀性.     

Electroless deposition of Ni–W–P–B4C nanocomposite coating on AZ91D magnesium alloy and investigation on its properties

In the present work, electroless deposition of quaternary Ni–W–P–B₄C composite coatings on AZ91D magnesium alloy was investigated. The coatings were characterized to study their microstructure, crystallite size, morphology, microhardness and corrosion resistance and compared with Ni–P and Ni–P–B₄C composite coatings, prepared with the same method. The hardness of the Ni–W–P–B₄C composite coatings was around 1290 MPa which was more than that of the Ni–P and Ni–P–B₄C coatings (about 700 and 1200 MPa, respectively). According to polarization test results, the Ni–W–P–B₄C composite coating exhibits less and more corrosion rates with respect to the Ni–P–B₄C and the Ni–P coatings, respectively. X-ray diffraction (XRD) analysis results for the Ni–W–P–B₄C coating showed that the Ni–W–P–B₄C coating has a combination of amorphous and nanocrystalline structures. Also, Williamson–Hall analysis on the X-ray patterns revealed that the Ni–W–P–B₄C coating has an average crystallite size of 1.5 nm.