脉冲电压幅值与电解液流动状态对无掩模定域性电沉积微镍柱的影响

为探究脉冲电压幅值与电解液流动状态对无掩模定域性电沉积微镍柱的影响,采用体视显微镜和扫描电子显微镜SEM对电沉积的微镍柱进行观察、检测,并计算了平均沉积直径和速率。在实验的基础上通过控制变量法研究了脉冲电压幅值与电解液流动状态对沉积微镍柱平均直径、平均沉积速率和表面形貌的影响。研究表明,当脉冲电压幅值在3.8~4.4 V时,电压幅值越大,微镍柱沉积速率越大,表面形貌越粗糙;平均沉积直径和速率会随电解液流动状态变化而发生改变,当流量在0.025~0.25 mm³/s时,沉积速率随电解液流量的增加而加快;电压由3.8 V增至4.4 V时,液滴、微液滴和微射流状态下微镍柱沉积直径增大,冲击射流状态下微镍柱直径则先增大后减小且微镍柱顶部呈明显的尖锥状并在镍柱周边存在"毛刺";微镍柱的表面形貌随电解液流动状态的不同而不同,大流量喷射(0.25 mm³/s)条件下,微镍柱表面更平整、致密。     

电沉积工艺参数对泡沫镍成形速度的影响

介绍了电解液喷射沉积制备泡沫镍的原理,讨论了相关电沉积参数对电沉积速度的影响,并且对影响因素进行了基础研究.结果表明,电流密度及电解液喷射速度与沉积速度呈线性关系,电流密度越大,成形速度越快;喷射速度越高,成形速度也越快;喷嘴口径大时,相应增大了电铸面积,提高了电铸的速度;电铸速度随喷嘴扫描速度的提高,略有下降.     

电沉积增材制造微镍柱的工艺研究

目的 探究电沉积工艺参数对无掩模定域性增材制造微镍柱的微观形貌、直径和沉积速率的影响.方法 采用尖锥形铂丝作为阳极、铜板作为阴极,电镀液从阳极和导流腔之间的微缝隙以射流方式流到阴极表面,电化学沉积增材制造微镍柱.采用体视显微镜和扫描电子显微镜对镍柱微观结构进行检测.通过单因素试验研究极间电压和初始极间距对微镍柱微观形貌、沉积速率和直径的影响规律.结果 初始极间距为10μm、电压为3.8～4.4 V时,可以制备出直径均匀、圆柱度较高的微镍柱;电压增至4.7 V时,微镍柱形状不规则,常伴有分叉现象或呈瘤状沉积.极间电压从3.8 V增加到4.7 V时,微镍柱体积沉积速率由539μm3/s增长至4159μm3/s,直径由55μm增长至102μm.此外,当极间电压为4.1 V、初始极间距为20～40μm时,随着初始极间距的增大,微镍柱顶端从圆柱形逐渐转向锥形沉积.结论 极间电压对微镍柱微观形貌、沉积速率和直径的影响明显,初始极间距主要影响微镍柱顶端的沉积生长形状.     

TiO2纳米管阵列生长进程及微观结构的研究

采用高纯度的Ti箔作为阳极,以Pt片为阴极,在0.1%～1.0%HF水溶液中,电压0.4～14.5 V,温度5～40℃范围内进行恒压阳极氧化制备TiO2膜.使用电化学工作站测试了线性扫描阳极极化曲线及阳极氧化过程中的电流密度-时间曲线;并使用扫描电子显微镜对氧化膜的平衡形貌进行观察;研究了阳极氧化时间、电压、电解液浓度以及温度对平衡生长氧化膜结构的影响.结果表明:阳极氧化工艺参数对氧化膜的形成速度、纳米孔孔径、纳米管阵列长度有显著影响.增大电解液浓度以及升高电解液温度,均有利于加快形成结构稳定的氧化膜,表现在到达氧化膜稳定生长的时间缩短,且平衡时纳米管的平均长度缩短.随电压增大,氧化膜生长加速,但获得平衡生长的时间相对延长;纳米孔孔径及纳米管的长度都随之增大.     

电泳沉积制备Ca10(PO4)6(OH)2/TiO2/Ti复合涂层

采用电泳沉积法在经阳极氧化的钛板表面形成羟基磷灰石涂层,研究了电解液浓度、电压、时间对氧化膜及涂层的影响,并进行了XRD和SEM表征。得出了阳极氧化的最佳工艺参数:电解液H2SO4的体积分数为20%,电压为120V,氧化时间为10min;电泳沉积的最佳工艺参数为:悬浮液的质量浓度为15g/L,沉积电压为250V,沉积时间为3min。     

离子液体[EMIM]Br-AlCl3中恒电流沉积铝

在磁力搅拌下,采用离子液体[EMIM]Br-AlCl3作为电解液并测其电导率,在不锈钢片上利用恒电流法电沉积铝,研究在AlCl3/[EMIM]Br摩尔比为2:1的离子液体中铝的电沉积速率、电流效率和阴极表面形貌的影响因素。采用扫描电子显微镜(SEM)分析沉积铝层的表面形态,采用X射线能谱仪(EDS)测试沉积铝的纯度。结果表明:离子液体[EMIM]Br-AlCl3的电导率随着温度的上升而增大,符合Arrhenius公式。电流密度,温度、搅拌速率和沉积时间均影响铝的沉积速率、电流效率和表面形貌。在电流密度为20 mA/cm2,温度为40℃,搅拌速率为700 r/min,时间为60 min的条件下,所得铝沉积层连续、致密、附着性好、颗粒状且粒径小;电流效率维持在80%以上,阴极铝层纯度达96%,其中少量的氧来自铝的氧化。     

金属镍枝晶射流电沉积中的可控生长

将分形理论引入到射流电沉积中,编程模拟了不同沉积几率时枝晶的生长形貌。基于模拟的原理,利用摆动射流电沉积,使金属离子更容易到达已沉积枝晶簇的内部而沉积,改变了枝晶的树枝状分形生长特性,制备了不同射流速度和电解液温度下的二维多孔交织的金属镍枝晶簇。结果表明：沉积几率的减小,使粒子簇的形貌转变为致密的多孔交织的组织。在摆动射流电沉积中,射流速度的增大,使枝晶簇的孔隙增大、组织均匀,多孔交织的形态更为明显。射流速度最大时,枝晶簇的形貌再次呈现致密型。分形维数随射流速度的增大逐渐减小。电解液温度的升高,使枝晶簇的形貌向致密型转变,分形维数逐渐增大。     

交流电压对AZ91D镁合金阳极氧化膜层的影响

在含有硅酸钠和硅溶胶的氧化溶液体系中,利用工频交流电源对AZ91D镁合金材料表面进行阳极氧化处理,同时探讨氧化电压对膜层表面形貌、生长速率和耐腐蚀性能等的影响规律.结果表明:氧化过程存在一个明显的临界电压值(170 V),在电压大于170V阳极氧化反应剧烈、氧化电流增大、试样表面出现弧光放电.当电压小于170 V时,镁合金表面则以均匀的桔黄色火花放电,获得的氧化膜层表面光滑、均匀、致密,而且膜层的生长速率和耐腐蚀性随着电压的增加而增大;当电压超过这个临界电压值时,获得的氧化膜层表面变得粗糙,其生长速率大幅提高,但膜层的耐腐蚀性能下降.     

高速喷射电沉积块体纳米晶C0-Ni合金

采用自制的高速喷射电沉积装置制备了块体纳米晶Co-Ni合金,利用SEM、TEM、XRD及EDS等方法研究了电流密度对沉积速率、电流效率及Co-Ni合金沉积层组织结构的影响,并与槽镀沉积层进行了对比.结果表明采用该方法后允许使用的极限电流密度、沉积速率及电流效率均显著增大,沉积速率高达47.33μm/min,是一般槽镀的90倍左右.随着电流密度的增加,沉积速率呈近似线性增加,但电流效率增大到一定值后基本不变.电流密度对沉积层成分影响不大,但明显减小沉积层的晶粒尺寸.与一般槽镀相比,晶粒尺寸由23.07nm减小到9.18nm.     

电解液温度对铝阳极合金电化学性能的影响

铝基阳极合金是一种有发展前途的电池用阳极材料,采用开路电位、极化曲线、电化学阻抗谱和恒电流放电曲线等测试方法,研究了电解液温度对铝阳极合金在4mol·L-1 NaOH溶液中电化学性能的影响。结果表明,随着电解液温度的升高,铝阳极合金的活化性能增强,其开路电位和工作电位明显负移,但合金的自腐蚀析氢速率增大。当温度为40℃时,合金表现出较好的综合性能和均匀的腐蚀形貌。     

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.