无氰电镀液中超声电沉积耐腐蚀纳米晶铜镀层

通过超声辅助电沉积法,在无氰络合电镀液中以高阴极电流密度在钕铁硼磁体上电沉积获得纳米晶铜防护镀层,研究了不同超声波频率下的镀层形貌、晶粒尺寸、显微硬度和耐腐蚀性能。结果表明,随着超声波频率的增加,络合电镀液体系的铜电沉积有效阴极电流密度显著增加,相应的阴极电流效率也提高,从而获得致密的纳米晶铜镀层。在阴极电流密度为4.0 A·dm^-2和超声波频率为40 kHz的条件下,能够获得平均晶粒尺寸为18.8 nm的铜镀层。超声辅助电沉积法还能促进烧结钕铁硼基体盲孔内的铜沉积,从而改善基体与镀层之间的结合力。在同样的镀层厚度下,烧结钕铁硼表面所沉积镀层的耐腐蚀性随超声波频率的提高而优化。     

激光同步辐照对电化学沉积铜组织结构及结合力的影响

目的 解决单一电化学沉积制备铜镀层沉积速度慢、沉积颗粒易团聚、晶粒生长不均匀及其与基体结合力差等问题。方法 采用沉积前激光处理、沉积过程激光同步辐照的方法,在316L不锈钢上制备铜涂层,通过光学显微镜、扫描电子显微镜、自动划痕仪分析了铜镀层表面形貌、截面厚度、涂层物相和结合力,探究了激光的增强作用和复合沉积技术下镀层的生长机制。结果 激光同步辐照促进了晶粒的高择优取向及沉积电位的正移。单一晶面的高择优取向利于提高镀层晶粒生长的均匀性,使镀层表面的凸起、孔洞明显减少,变得平整致密。同时,激光同步辐照使镀层表面粗糙度维持在一个较低的范围,使沉积质量不会随沉积时间的增加而降低,有利于电化学沉积的继续进行,实现镀层增厚。相同沉积时间(60 min)下,传统电化学沉积所得镀层的沉积厚度为62.62μm,表面粗糙度为4.741μm;而激光同步复合电化学沉积所得镀层的沉积厚度为138.39μm,表面粗糙度为0.995μm;且镀层表现出与基体更佳的结合力,与基体间的极限载荷可达98.2 N。结论 激光同步辐照提高了铜镀层的沉积效率、质量及其与基体间的结合力。     

1-丁基-3-甲基咪唑四氟硼酸盐离子液体电沉积制备Ir研究（英文）

研究了在离子液体1-丁基-3-甲基咪唑四氟硼酸盐中电沉积制备Ir的电化学行为,在金电极上获得的循环伏安特性曲线显示,Ir(Ⅲ)经过一步还原反应生成Ir,并且该反应是由Ir(Ⅲ)离子的扩散控制的不可逆过程。其中,扩散速率为3.83×10-11 m~2/s,平均传质系数为0.083。用扫描电镜(SEM)、X-射线衍射(XRD)及X-射线光电子能谱(XPS)研究了在钼基体上获得的Ir层的表面形貌及组成,结果表明,Ir层的形貌与沉积电位、时间及电流密度有关。恒电位电沉积过程中,在还原峰电位处由于成核及生长速率达到平衡,可以获得相对致密的镀层。在恒电流电沉积中,当电流密度在0.5~1.82 mA/cm~2时,可以得到平整致密的Ir镀层。     

导电塑料表面电化学镀镍和镀层表征

为了提高导电塑料的表面硬度、强化表面导电行为,采用电沉积的方法在导电塑料上镀镍,研究了镀液温度、电镀时间和阴极电流密度对镀层厚度增长速度的影响,利用扫描电镜和金相显微镜对镀层进行了表征,采用粘结拉脱法测量了镀层与基体之间的结合力,采用电化学方法研究了镍镀层在NaCl水溶液中的腐蚀行为.结果表明:阴极电流密度为2.0A/dm2、镀液温度为60℃时,可以得到0.68μm/min的平均镀层增长速率;镍镀层可以保留导电塑料基体的表面特征,镍镀层与基体之间结合力可以达到2.3MPa以上;光亮镍镀层在NaCl水溶液中的腐蚀电位高于哑镍镀层的腐蚀电位,且在相同的极化电位下,光亮镍镀层阳极溶解速率也较低.     

离子液体AlCl_3-[bmim]Cl中电沉积铝的研究

在摩尔比为2:1的AlCl_3-[bmim]Cl离子液体中,加入一定量的甲苯,控制阴极电流密度,在基体铁片上获得银白色和平整致密的铝镀层。循环伏安实验表明离子液体中沉积铝源于Al_2Cl_7~-的还原,还原峰电位为-0.34V;当电流密度为20mA/cm~2时,最大电流效率达97%;所得铝镀层的厚度与电镀时间呈抛物线关系;在电流密度小于35mA/cm~2时,镀层厚度随电流密度增大呈逐渐递增趋势;扫描电镜、X射线能谱对铝镀层分析结果表明(45±2)℃温度得到平整致密纯度高的铝镀层;当电流密度为20mA/cm~2时,铝镀层呈薄片状生长,随电流密度的增大,镀铝层形貌由片状向粒状过渡,并伴随着晶粒的细化。     

电流密度对电沉积铜膜剩余电阻率的影响

为了获得1.3 GHz功率耦合器的镀铜膜,研究不同电流密度和沉积时间对镀铜膜剩余电阻率(RRR)的影响。电流密度分别为1、1.5和2 A/dm~2,沉积时间为1～6 h,讨论了铜膜RRR值、微观形貌、表面粗糙度和织构随镀层厚度的变化。结果表明,随着电流密度减小和沉积时间延长,表面粗糙度变大,铜膜RRR值增大。在电流密度为1和1.5 A/dm~2下沉积的铜膜,随着沉积时间的增加,晶胞结节变大,(111)晶面的织构系数增加,铜膜RRR值变大。在电流密度为2 A/dm~2下沉积的铜膜中含有孔洞缺陷,导致铜膜的RRR值显著下降。硬X射线自由电子激光装置的1.3 GHz功率耦合器的铜膜采用电流密度为1 A/dm~2,沉积时间为4 h的镀铜工艺,其铜膜RRR值、铜膜与基体结合力、高低温适应性以及微波功率均满足实际工程应用。     

含疏水性液体微胶囊复合铜镀层的制备与性能研究

采用水相分离法制备了以甲基硅油为囊芯、聚乙烯醇为囊壁的疏水性液体微胶囊,并以其作为电沉积组分,研究渐变电流密度下的复合铜镀层电沉积工艺,对所制备的复合铜镀层表面微观形貌和疏水性进行表征,同时考察镀层在酸性腐蚀环境下对基体的保护效果。结果表明,所制备的含液体微胶囊复合铜镀层较纯铜镀层结晶更加致密;H₂O在其表面的润湿性下降,接触角从90° 增大至131°;复合镀层在1%(质量分数) H₂SO₄溶液中的自腐蚀电流密度较纯铜镀层降低3个数量级,自腐蚀电位由-0.63 V正移至-0.27 V,显示出良好的耐蚀性。     

TC4钛合金铜镀层的性能*

传统的氰化物镀铜工艺会对环境造成极大的危害,钛合金无氰镀铜技术具有较高的研究价值。采用无氰化物硫酸盐镀铜技术在TC4钛合金表面制备铜镀层,利用扫描电子显微镜和能谱仪对其镀层形貌、成分、结合力、磨损形貌进行分析,并利用电化学方法和摩擦磨损试验研究其抗蚀性与耐磨性。结果表明:无氰化物镀铜技术在TC4钛合金表面电镀铜可获得表面均匀致密,结合力良好的镀层;TC4钛合金表面电镀铜后,摩擦因数由0.520降至0.381,可见钛合金表面铜镀层通过减摩作用能有效的改善和提高其耐摩擦磨损性能。TC4钛合金镀铜和未镀铜表面均存在钝化区,两者维钝电流密度分别为1×10-2 A/cm2和4×10-5 A/cm2,均有较好的抗腐蚀性能,TC4钛合金镀铜后的表面抗腐蚀性能较基体有所降低。     

1-丁基-3-甲基咪唑四氟硼酸盐离子液体电沉积制备Ir研究

本文研究了在离子液体1-丁基-3-甲基咪唑四氟硼酸盐中电沉积制备Ir的电化学行为,在金电极上获得的循环伏安特性曲线表示,Ir(III)经过一步还原反应生成Ir,并且该反应是由Ir(III)离子的扩散控制的不可逆过程。其中,扩散速率为3.83×10_?11 m₂/s,平均传质系数为0.083。本文用扫描电镜(SEM)、X-射线衍射(XRD)及X-射线光电子能谱(XPS)研究了在钼基体上获得的Ir层的表面形貌及组成,结果显示,Ir层的形貌与沉积电位、时间及电流密度有关。恒电位电沉积过程中,在还原峰电位处由于成核及生长速率达到平衡,可以获得相对致密的镀层。在恒电流电沉积中,当电流密度在0.5~1.82 mA/cm₂时可以得到平整致密的Ir镀层。     

Al-Mg合金镀层的制备与性能

利用AlCl3 LiAlH4 MgBr2有机溶剂体系在碳钢基体上电沉积出Al-Mg合金镀层,并对不同沉积电流密度下Al-Mg镀层的表面形貌、成分、结构、厚度、结合力和耐蚀性进行了研究。结果表明:沉积出的铝镁合金镀层表面光滑、均匀、致密;膜层中的镁含量随沉积电流密度的增加而增大,且以Al-Mg固溶体形式存在,并按(200)面的结构生长;随沉积电流密度的增加,铝镁合金镀层的厚度与晶格常数呈线性增大;在3.5%NaCl溶液中的耐蚀性呈先增大后减小的规律;Al-Mg镀层与碳钢基体的结合力良好,均大于50 N;Al-Mg镀层的沉积速率、结合力和耐蚀性均高于相同沉积条件下的纯铝镀层;Al-Mg合金镀层沉积的最佳电流密度为0.75~1.50A/dm2。     

Effects of Post-weld Heat Treatment on Microstructure,Mechanical Properties and the Role of Weld Reinforcement in 2219 Aluminum Alloy TIG-Welded Joints

In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.     

The First Phase of the SRIF Industrialized Base in ＂West Area＂ Has Been Put into Operation

After nearly two years＇ tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry （SRIF）, located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.     

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。     

Effect of Rare Earth Doping on Impedance,Modulus and Conductivity Properties of Multiferroic Composites:0.5(BiLa_xFe_(1-x)O_3)–0.5(PbTiO_3)

The Lanthanum-doped bismuth ferrite–lead titanate compositions of 0.5(Bi LaxFe1-xO3)–0.5(Pb Ti O3)(x = 0.05,0.10,0.15,0.20)(BLxF1-x-PT) were prepared by mixed oxide method.Structural characterization was performed by X-ray diffraction and shows a tetragonal structure at room temperature.The lattice parameter c/a ratio decreases with increasing of La(x = 0.05–0.20) concentration of the composites.The effect of charge carrier/ion hopping mechanism,conductivity,relaxation process and impedance parameters was studied using an impedance analyzer in a wide frequency range(102–106Hz) at different temperatures.The nature of Nyquist plot confirms the presence of bulk effects only,and non-Debye type of relaxation processes occurs in the composites.The electrical modulus exhibits an important role of the hopping mechanism in the electrical transport process of the materials.The ac conductivity and dc conductivity of the materials were studied,and the activation energy found to be 0.81,0.77,0.76 and 0.74 e V for all compositions of x = 0.05–0.20 at different temperatures(200–300 °C).     

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.     

Quantitative Analysis of the Crystallographic Orientation Relationship Between the Martensite and Austenite in Quenching–Partitioning–Tempering Steels

The orientation relationships(ORs)between the martensite and the retained austenite in low-and medium-carbon steels after quenching–partitioning–tempering process were studied in this work.The ORs in the studied steels are identified by selected-area electron diffraction(SAED)as either K–S or N–W ORs.Meanwhile,the ORs were also studied based on numerical fitting of electron backscatter diffraction data method suggested by Miyamoto.The simulated K–S and N–W ORs in the low-index directions generally do not well coincide with the experimental pole figure,which may be attributed to both the orientation spread from the ideal variant orientations and high symmetry of the low-index directions.However,the simulated results coincide well with experimental pole figures in the high-index directions{123}_(bcc).A modified method with simplicity based on Miyamoto’s work was proposed.The results indicate that the ORs determined by modified method are similar to those determined by Miyamoto’method,that is,the OR is near K–S OR for the low-carbon Q–P–T steel,and with the increase of carbon content,the OR is closer to N–W OR in medium-carbon Q–P–T steel.     

The Mirror with Patterns of Auspicious Animals and Grapes——Exquisite cast mirror and the technology of surface tin-enrichment by rubbing-in and infiltration of tin-rich powder

<正>Bronze mirrors were used by the Chinese people before the introduction of the glass mirror.Only after it was replaced by the glass mirror did the bronze mirror gradually retreat from people's lives.Different styles of bronze mirrors were made in different historical periods,particularly in the Warring States Period,the Han and Tang Dynasties,which were the three peaks of the development of bronze mirror arts in ancient China.The casting techniques were exquisite.The surface of the bronze mirror was smooth and bright enough to reflect one's image,and there were scarcely any casting defects on the mirror surface.On the back of the bronze mirror,there were rich depictions of Arts and Humanities,and the ornamentations were also     

The 9th China International Diecasting Congress & Exhibition

The 9th China International Diecasting Congress ＆ Exhibition was held on July 22-24, 2014 at Shanghai New International Expc Centre. This exhibition was the most successful over the years, with over 6890 visitors and 155 exhibitors, and the exhibition area increased by 30% from 9,500 square meters in 2012 to 12340 square meters. Die casting enterprises from a total of 24 countries and regions, including China mainland, Chinese Taiwan and Hong Kong, South Korea, Japan, Germany, India, Thailand, Malaysia, the United States, Russia, Australia, Iran, Ukraine, Brazil, Colombia, Singapore, Austria, Canada, Croatia, France, Turkey, United Kingdom, Vietnam, attended the congress and exhibition.     

Introduction of the Fluid Control Engineering Institute of Kunming University of Science and Technology

正The Fluid Control Engineering Institute of Kunming University of Science and Technology was set up in 1996.The researches of institute concentrate on electro-hydraulic(pneumatic)servo/proportional control and hydromechatronics.The Institute is committed to research and development of electro-hydraulic control of high-end technical equipment in ferrous metallurgy refining produc-     

RARE METALS Volume Contents

正~~