复合还原剂SHP和HAS对Ni-P表面还原镀金的影响

目的 研究复合还原剂次亚磷酸钠（SHP）和硫酸羟胺（HAS）对置换镀金过程的影响,拟解决化学镀Ni-P层上置换镀金的镍腐蚀和后期沉金困难的问题。方法 采用连续加热测试,研究了还原剂对镀液稳定性的影响。利用密度泛函理论对配合物分子进行了计算,对比了反应前后配合物分子结构的福井函数和轨道能级。通过XRF测试了金层的厚度,并结合开路电位分析了还原剂对镀层厚度的影响。利用恒电位下电流瞬变对金核生成和成长的影响进行了分析。通过SEM对镀层的微观形貌进行了表征;通过Tafel测试对镀层的电化学抗腐蚀性进行了分析。结果 次亚磷酸钠和硫酸羟胺同时加入不会影响镀液的稳定性,羟胺与腈根的反应降低了Au+的反应活性。0.05 mol/L次亚磷酸钠和0.03 mol/L硫酸羟胺下能够获得超过0.09 μm的镀金层。在次亚磷酸钠的作用下,镀金过程中的镍析出减少,镍层的腐蚀得到有效抑制。成核模式在硫酸羟胺的作用下处于瞬时成核,金核尺寸更大。镍腐蚀的减少以及镀金层厚度的增加,使得整个镀层的抗腐蚀性能得到显著的提高。结论 在置换镀金液中同时加入次亚磷酸钠和硫酸羟胺有效地提升了镀金速率,并且降低了镍层腐蚀,改善了化学镀镍金层的质量,有利于提高工业生产效率,并满足PCB高致密性和高频化趋势下的新要求。     

脉冲镀金工艺研究进展

金镀层具有良好的耐腐蚀性、抗氧化性、导电性及延展性,广泛应用于精密微纳元器件制造。电化学镀金是实现微纳元器件镀金的主要工艺之一,主要分为直流镀金工艺和脉冲镀金工艺。相较于直流镀金工艺,脉冲镀金工艺可通过控制脉冲波形、频率、占空比及电流密度等脉冲参数,改变金属离子电沉积过程中的电化学极化和浓差极化,灵活调控镀层的物理化学性能。近年来,国内外在微纳元器件脉冲镀金工艺领域开展了系列研究工作,并取得了不错的进展。综述了电化学脉冲镀金的基本原理,描述了电镀金试验中金由离子形态转化为金属的过程。此外,还综述了占空比、频率、电流密度、脉冲导通时间、脉冲关断时间等脉冲参数对金镀层形成的影响,以及镀层性能评价方式;另外,介绍了无氰和有氰两大典型镀液获得金镀层的基本情况,分析了它们各自的优缺点,主要表现为有氰镀液稳定性好,所得金镀层较均匀,而无氰镀液的突出优势为无毒,但其稳定性有待进一步提高。最后,展望了脉冲镀金工艺的发展方向,可为发展新型脉冲镀金工艺及应用拓展提供有益的参考和启示。     

电子工业中电沉积金镀层的应用与发展

金镀层具有良好的导电性、耐腐蚀性、稳定性等特点,在半导体、集成电路、电子元器件产品等方面具有重要的应用价值。随着电子产品零件表面镀金的重要性日益提升,国内外一直在提高镀金工艺技术的稳定性、镀层功能性方面进行了大量研究,而且在多种电子工业产品中的关键镀金技术研究方面开展的工作也越来越深入。从不同的角度综述了目前电子及相关行业中应用电镀金层及电镀金技术的情况,探讨了电镀金层及电镀金技术在电子工业领域的应用进展,分析了在不同基体材料表面沉积金层的技术(如制作薄膜基板的导带、线路板的接地通孔及上下层互连通孔、键合点、焊盘及空气桥等),介绍了镀金层的主要功能(如抗变色和抗化学腐蚀性能,低的接触电阻和导电性,高温下的抗氧化性能,贮存过程中的焊接性能,物理、机械性能等)。对电子行业现代化带动镀金技术的发展与需求,提出了开发和应用无氰镀金技术以及学科交叉对促进镀金技术发展的趋势,肯定了镀金技术对电子领域科技进步的贡献。     

工艺参数对钨丝表面无氰镀金质量的影响

为了实现钨螺旋线表面镀金薄膜质量可控,研究了无氰电镀过程中工艺参数如电流密度、镀液温度和沉积时间对镀金层质量的影响规律。利用扫描电子显微镜对镀金层形貌进行观察分析。结果表明:电流密度影响镀金薄膜的表面平整度及晶粒大小;镀液温度影响无氰镀液稳定性,从而影响薄膜的表面光泽度及平整度;电沉积时间对镀层覆盖效果影响较大。沉积时间过短,镀层覆盖效果差;时间过长,边角效应严重。沉积时间宜控制在1.5 h内。     

过渡层对钨螺旋线表面无氰镀金质量的影响

采用预镀过渡层的方法提高钨螺旋线表面无氰镀金薄膜质量,研究了过渡层厚度对镀金层质量的影响。利用带有能量色散光谱仪的扫描电子显微镜对镀层形貌和成分进行了分析。结果表明:预镀层厚度对镀金层质量有影响。预镀层过薄,影响后续镀金层覆盖效果,导致螺旋线表面部分裸露;预镀层过厚,氢炉高温(960℃,0.5 h)处理过程中可形成铜含量较高的Cu-Au合金易熔化,镀金层出现起皮、脱落等现象。沉积时间控制在10 s时可获得适宜厚度的过渡层。     

聚乙烯亚胺对置换镀金过程中镍基体腐蚀的影响

通过)XRF、SEM、XPS、开路电位、极化曲线、电化学阻抗谱及红外漫反射等方法,分析了聚乙烯亚胺对置换镀金过程中镍基体腐蚀的影响原因.结果表明:聚乙烯亚胺降低了置换镀金初始时沉积速率,而对长时间施镀镀速的影响较小;聚乙烯亚胺降低了金层Ni、O元素的含量;该添加剂能够在镍、金表面吸附,而且优先在金表面吸附,并加速了镍表面氧化物的溶解速率.聚乙烯亚胺使化学镀镍层表面活性趋于一致,减轻了镍基体的过度腐蚀现象.     

钯镍合金电镀

一、前言当前国际黄金价格剧升,而电子产品镀金量迅猛增加;为缓和矛盾,近几年西方国家大力开展代金镀层的研究。综合国外文献报导,钯镍合金(80钯/20镍)镀层的技术指标与镀金层相近,且价格较廉,因而在电子产品的接插件、印制板、三极管等应用领域内作为代金镀层。此外,钯镍合金镀层外观呈光亮、柔和的银白色,美观大方,硬度高,抗变色性能好,在高档装饰品方面也具有一定市场. 我们从一九八四年初起,就开始进行代金镀层的研制,于四月份镀出钯镍合金簧     

一种无氰化学镀金工艺的研究

为了确定一种无氰亚硫酸金钠化学镀金的最佳工艺条件,并使其具有工业上的可行性,利用镀层厚度测试和镀层结合力测试等性能检测手段,研究了该工艺中镀液组分和操作条件对镀层的影响.结果表明:当溶液中亚硫酸金钠(以金计)为 1～3g/L,亚硫酸钠为13g/L,按乙二胺/Au=(6～10)∶〖KG-*2/3〗1比例投入,磷酸氢二钾为30g/L,pH为8～9,温度为50～60℃时,可以得到光亮均匀的镀金层.     

温度对碳化硅粉体表面镀镍的影响

为改善碳化硅陶瓷粉体与金属的润湿性,在碱性条件下,以水合肼为还原剂,采用化学镀方法在 碳化硅粉体表面沉积镍层,结合镀层的表面形貌、组织结构和实验现象,研究了镀液温度对镀镍的影响,此外还研究了水合肼用量对镀速的影响.结果表明:反应温度为70,75,80℃时,所得包覆粉体的表面镀层由颗粒状、胞状的Ni组成,基体完全被镀层...     

SiO 2基底上化学镀Ni-Mo-P薄膜的生长和形成机理

采用化学镀方法在SiO2/Si 基底上制备Cu互联线用阻挡层材料Ni-Mo-P薄膜。采用场发射扫描电子显微镜、电子分散能谱仪、原子力显微镜分析不同沉积时间样品的表面形貌和成分,并对Ni-Mo-P薄膜的形成过程进行研究。Ni-Mo-P薄膜的形成过程分为3个阶段：催化阶段,先前还原的Pd颗粒成为Ni还原的催化形核中心,诱导Ni沉积;覆盖阶段,Ni颗粒诱导Mo、P与之进行共沉积;自生长阶段,Ni-Mo-P薄膜共同沉积,颗粒生长。阐述了还原剂被氧化后产物为3-4PO 的的反应机理。     

新型的治疗阿尔茨海默氏症药物(1-二甲基磷酰基-2,2,2-三氯)-乙基-1-醇烟酸醋对体外神经细胞的作用

目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基^-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L^-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L^-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L^-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。     

Three-Dimensional Growth of Coherent Ferrite in Austenite: A Molecular Dynamics Study

Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems.     

Rheology Feature of Simple Metal Melt

The rheology feature of Sb, Bi melt and alloys was studied using coaxial cylinder high-temperature viscometer. The results showed that the curve of torsion-rotational speed for Sb melt presents a linear relation in all measured temperature ranges, whereas for the Bi melt, the curve presents obvious non-Newtonian feature within the low temperature range and at relative high shear stress. The rheology feature of Sb80Bi20 and Sb20Bi80 alloy melts was well correlated with that of Sb and Bi, respectively. It is considered that the rheology behavior of Sb melt plays a crucial role in Sb80Bi20 alloy and that of Bi melt plays a crucial role in Sb20Bi80 alloy.     

Effect of Short-Time Aging on the Pitting Corrosion Behavior of a Novel Lean Duplex Stainless Steel 2002

The effect of short-time aging in the temperature range between 400 and 1000 °C on the pitting corrosion behavior and mechanical property of a novel lean duplex stainless steel(LDSS) 2002 was investigated through the potentiostatic critical pitting temperature(CPT) tests and the Charpy impact tests. Both the pitting corrosion resistance and the toughness of aged specimens degraded due to the precipitation of detrimental secondary phases and the most significant reduction of CPT and impact energy emerged at 650 °C concurrently. The CPT of LDSS 2002 specimen aged at 650 °C decreased by 28 °C, and the impact energy dropped from 69 to 29 J/cm~2 compared with the solution-annealed sample. Transmission electron microscopy characterization showed that the main precipitates in LDSS 2002 were Cr_2N and M_(23)C_6 along the ferrite–austenite grain boundaries.     

INTRODUCTION TO PATENTS

The invention provides a method of making a mold which can reduce SOx generation rate while preventing decrease in hardening rate in the case of using sulfuric acid for a hardener composition. The method has a mixture step in which fire-resistant particles, a hardener composition and a binder composition are mixed to obtain a composition for a mold. The hardener composition contains sulfuric acid. In the mixture step, sodium carbonate is added. A molar ratio of the sulfuric acid to the sodium carbonate is 0.5 or more and 4.0 or less.     

China Foundry Week 2014

China Foundry Week, hosted by the Foundry Institution of Chinese Mechanical Engineering Society （FICMES） each year, is a large academic event in China. It is one of the ten high-impact activities sponsored by the Chinese Mechanical Engineering Society.     

17th Conference of Hydrodynamic and Electromechanical Control Engineering Call for papers

正1.Contents In order to promote the academic exchanges and technical communication of the research in the field of fluid power transmission and control,fluid control engineering specialized committee of the Chinese Society of Theoretical and Applied Mechanics will hold the 17th Conference of Hydrodynamic and Electromechanical Control Engineering on July 27-29,2014 in Tibet,Lhasa city.     

Information for Contributors

正The Transactions of Nonferrous Metals Society of China,founded in 1991 and sponsored by The Nonferrous Metals Society of China,is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology,including mineral processing,extraction metallurgy,metallic materials and heat treatments,metal working,physical metallurgy,powder metallurgy,with the emphasis     

Preface

<正>We are pleased to present this Special Issue of Transactions of Nonferrous Metals Society of China containing selected papers from the First Asian Conference on Aluminum Alloys(ACAA-2013),held in Beijing,China,13–17 October 2013.This conference has been initiated,with approval of     

Information for Contributors

The Transactions of Nonferrous Metals Society of China, founded in 1991 and sponsored by The Nonferrous Metals Society of China, is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology, including mineral processing, extraction metallurgy, metallic materials and heat treatments, metal working, physical metallurgy, powder metallurgy, with the emphasis on fundamental science. It is the unique preeminent publication in English for scientists, engineers, under/post-graduates on the field of nonferrous metals industry. This journal is covered by many famous abstract/index systems and databases such as SCI Expanded, Ei Compendex Plus, 1NSPEC, CA, METADEX, AJ and JICST.