磁场作用下电沉积镍层织构及表面形貌分析

分别在垂直和平行磁场环境下电沉积镍,利用XRD和SEM研究了电流密度、磁场强度、磁场方向、超声强度对镍晶镀层织构,以及磁场强度对镀层表面形貌的影响作用,并对其影响机理进行了分析。结果表明:增大电流密度对(200)晶面取向具有促进作用,随着电流密度的增大,晶面织构由以(111)为主变为以(200)为主;磁场强度增加会促使镀层织构(111)晶面取向增强,平行磁场相较于垂直磁场更有利于晶粒生长;超声作用会使晶粒由择优取向变为随机取向;此外,施加磁场作用后,晶粒尺寸随磁感应强度增加而减小,表面更加均匀。     

电流密度对镍镀层结构和性能的影响

采用阴极移动电镀技术在电流密度为1～13A/dm2时制备镍镀层。利用扫描电镜(SEM)、X射线衍射仪(XRD)、X射线应力衍射仪以及硬度计等手段,研究电流密度对镍镀层的表面形貌、结晶取向、孔隙率、内应力和硬度的影响。结果表明:镍镀层的织构和性能随电流密度的变化而改变。当电流密度低于7A/dm2时,镀层表面球形颗粒较为粗大、孔隙率较高,在为4A/dm2时,镀层具有最低的拉应力约110 MPa;当电流密度为7A/dm2时,镀层表面球形颗粒均匀细小,具有最小的表面粗糙度Ra 0.69μm,最小的孔隙率0.08个/cm2以及最高的硬度330HV0.1;当电流密度大于7A/dm2时,镀层的表面粗糙度增加,择优取向由(200)晶面向(220)晶面发生转变,电流密度达到13A/dm2时,(220)晶面的织构系数达到了85.4%。     

氯化胆碱-乙二醇低共熔溶剂中电沉积纳米晶镍

采用循环伏安和计时电流技术考察氯化胆碱-乙二醇低共熔溶剂中镍在铂电极上的电沉积行为,利用扫描电子显微镜及X射线衍射技术研究电流密度对镍镀层形貌及织构变化的影响。结果表明:镍在氯化胆碱-乙二醇低共熔溶剂中的电沉积过程是准可逆的,其形核/生长过程遵循Scharifker-Hill三维形核模型。初始阶段,镍离子的形核/生长过程按三维连续形核机制,随后趋向于三维瞬时形核机制。随电流密度的增大,镀层厚度增加,晶粒尺寸减小,镍(111)晶面择优取向减弱,镀层表面形貌则由锥形颗粒状变为不规则的多面体颗粒状,最后变为圆球形胞状结构。     

三氯化铝/盐酸三甲胺离子液体中电沉积制备AI-Ni合金镀层

目的 研究离子液体中Ni2+浓度对Al-Ni合金镀层结构和成分的影响,同时考察电流密度对镀层表面形貌和织构的影响.方法 采用脉冲电流法,在含有不同浓度氯化镍的无水三氯化铝/盐酸三甲胺离子液体中,于不同电流密度下电沉积制备Al-Ni合金镀层.利用扫描电子显微镜、X射线衍射技术和能谱分析仪探究离子液体中Ni2+的浓度对Al-Ni合金镀层结构和成分的影响,考察电流密度对镀层表面形貌和织构的影响.结果 随着离子液体中Ni2+浓度的增加,镀层中镍的含量增多,表面胞状颗粒逐渐变小,表面趋于均匀,当Ni2+的浓度为0.2 mol/L时,形成铝镍金属间化合物.另外,随着电流密度的增加,镀层表面形貌由针状晶体变为棒状颗粒,并且颗粒逐渐增大.结论 离子液体中Ni2+的浓度和电流密度对Al-Ni合金镀层表面形貌、结构和成分有一定的影响.当溶液中Ni2+的浓度为0.2 mol/L、电流密度为6 mA/cm2时,电沉积4 h可制备得到厚度为10μm、由3μm大小晶粒组成、含有铝镍金属间化合物的合金镀层.     

三氯化铝/盐酸三甲胺离子液体中电沉积制备Al-Ni合金镀层

目的研究离子液体中Ni~(2+)浓度对Al-Ni合金镀层结构和成分的影响,同时考察电流密度对镀层表面形貌和织构的影响。方法采用脉冲电流法,在含有不同浓度氯化镍的无水三氯化铝/盐酸三甲胺离子液体中,于不同电流密度下电沉积制备Al-Ni合金镀层。利用扫描电子显微镜、X射线衍射技术和能谱分析仪探究离子液体中Ni~(2+)的浓度对Al-Ni合金镀层结构和成分的影响,考察电流密度对镀层表面形貌和织构的影响。结果随着离子液体中Ni~(2+)浓度的增加,镀层中镍的含量增多,表面胞状颗粒逐渐变小,表面趋于均匀,当Ni~(2+)的浓度为0.2 mol/L时,形成铝镍金属间化合物。另外,随着电流密度的增加,镀层表面形貌由针状晶体变为棒状颗粒,并且颗粒逐渐增大。结论离子液体中Ni~(2+)的浓度和电流密度对Al-Ni合金镀层表面形貌、结构和成分有一定的影响。当溶液中Ni~(2+)的浓度为0.2 mol/L、电流密度为6 m A/cm~2时,电沉积4 h可制备得到厚度为10μm、由3μm大小晶粒组成、含有铝镍金属间化合物的合金镀层。     

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。     

电镀工艺对镍纳米膜微观结构及硬度的影响

采用直流电沉积法制备纳米晶镍膜,研究了添加剂C12H2NaSO4,TJ,GL-100对镀层微观表面形貌、硬度、晶粒尺寸及织构的影响,同时探讨了电流密度对硬度的影响。结果表明：在无添加剂和仅加入C12H25NaSO4时,改变了镀层晶面的生长速率和晶粒快速的生长方向,使（200）晶面发生织构;TJ的添加显著细化晶粒;TJ和GL-100复合添加使镀层晶粒在（111）晶面择优取向生长。3种添加剂的复合作用,使镀层表面形貌及硬度达到最佳状态。在电镀条件相同时,镀层的硬度随电流密度的增加而增加。     

镀液温度对电化学制备Ni-SiC纳米复合镀层微观结构的影响

在不同镀液温度下直流电沉积制备Ni-SiC纳米复合镀层,利用X-射线衍射仪(XRD)、扫描电子显微镜(SEM)和能谱仪(EDX)对镀层的相组成、表面形貌、成分等进行表征,考察镀液温度对镀层的微观形貌、晶体生长和镀层中SiC含量等影响。结果表明:随着温度升高,Ni-SiC晶粒从无序取向渐变为(220)择优取向,到70℃时(220)面的晶面织构系数达到最大值;镀层中纳米SiC含量随着温度的升高先增大后减少,在60℃时达到最大值;纳米SiC微粒的加入可抑制镍晶的晶粒生长,从而细化晶粒,并使镍晶产生晶格畸变;Ni-SiC纳米复合镀层的表面形貌随温度的升高,表面颗粒更加细化和均匀。     

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。     

电流密度对声电沉积生物活性透钙磷石涂层结构和形貌的影响

通过声电沉积工艺在碳／碳复合材料表面制备了生物活性透钙磷石涂层，采用SEM、FFIR、XRD研究了超声场中电流密度对涂层组成结构和形貌的影响。发现在一定工艺条件下，随电流密度增加，涂层的平均晶粒尺寸减小，致密度增加；当电流密度小于l0mA／cm^2时涂层形貌为片状，l0mA／cm^2-26mA／cm^2时为粒状，32mA／cm^2时为花菜心状。且涂层中透钙磷石晶体的择优取向也发生变化，择优晶面依次为(021)、(111)、(220)。同时还讨论了涂层微观结构变化机理。     

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。     

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.     

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).     

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

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