Cathodic micro-arc electrodeposition of yttrium stabilized zirconia （YSZ） coatings on FeCrAI alloy

The formation of ceramic coatings on metal substrate by cathodic electrolytic deposition (CELD) has received more attention in recent years. But only thin filmscan be prepared via CELD. Yttrium stabilized zirconia (YSZ) ceramic coatings were deposited on FeCrAI alloy by a novel technique--cathodic micro-arc electrodeposition (CMED).The result shows that, when a high pulse electric field is applied to the cathode which was pre-deposited with a thin YSZ film, dielectric breakdown occurs and micro-arc discharges appear. Coatings with reasonably thickness of-300μm and crystalline structure can be deposited on the cathode by utilizing the energy of the micro-arc. The thickness of the as-deposited coating is dominated by the voltage and the frequency. Y2O3 is co-deposited with ZrO2 when Y(NO3)3 was added to the electrolyte, which stabilize t-phase, t′-phase and c-phase of ZrO2 at room temperature. The amount of the m-ZrO2 in the coating is diminished by increasing the concentration of Y(NO3)3 in the electrolyte.This report describes the processing of CMED and studies the microstructure of the deposited YSZ coatings.     

Microstructure and mechanical properties of a novel Zr-based bulk metallic glass composite

Zr48.5Cu46.5Al5 bulk metallic glass （BMG） composites with diameters of 3 and 4 mm were prepared through suction casting in an arc melting furnace by modulating the alloy composition around the monothetic BMG composition of the high glass forming ability. Microstructural characterization reveals that the composites contain micron-sized CuZr phase with martensite structure, as well as nano-sized Zr2Cu crystalline particles and Cu10Zr7 plate-like phase embedded in an amorphous matrix. Room temperature compression tests showed that the composites exhibited significant strain hardening and obvious plastic strain of 7.7% for 3 mm and 6.4% for 4 mm diameter samples, respectively.     

Preparation and Adsorption Ability of Polysulfone Microcapsules Containing Modified Chitosan Gel

Chemically modified chitosan beads containing polyethyleneimine （PEI） were prepared to improve the metal ion adsorption capacity of the chitosan beads and their mechanical stability and to limit their biodegradability. The modified beads were encapsulated with the polymer material polysulfone by a novel surface coating method named the emulsion phase inversion method. The adsorption properties of the modified beads and the microstructures of the polysulfone coating layer were then analyzed. The experimental results showed that the PEI was successfully linked onto the chitosan beads. The density of the -NH2 groups in the modified beads was significantly increased, while the water content was reduced. The coating layer thickness was about 200 pm. The modified chitosan gel beads had excellent Cu（ll） adsorption capacity, with a maximum Cu（ll） adsorption capacity 1.34 times higher than that of the unmodified beads. The results show that even with the polysulfone coating the adsorption kinetics of the modified beads is still better than those of the unmodified beads. The modifications improve the mass transfer performance of the chitosan beads as well as the bead stability.     

NiCrAlY涂层/TC4基体界面反应机理

采用电弧离子镀技术在TC4(Ti6Al4V)合金基体表面沉积制备NiCrAlY涂层.通过扫描电镜与能谱分析、X射线衍射分析及显微硬度测试,研究真空热处理对NiCrAlY涂层组织性能的影响;分析界面反应产物的形成过程;讨论Cr元素在界面反应中的作用机制.研究结果表明:真空热处理后NiCrAlY涂层中有γ'-Ni3Al相析出,提高了涂层的表面硬度;在870℃以下热处理,NiCrAlY涂层/TC4基体界面反应产物的出现顺序依次为:相变影响区→Ni3(Al,Ti)和Ti2Ni化合物层→TiNi化合层;Cr元素在870℃以上开始扩散并参与界面反应,形成TiCr2化合物.     

泡沫金属的力学性能研究综述

详细综述了泡沫金属的拉伸、压缩、能显吸收、应变率敏感性等力学性能，以及孔径、基体材料、温度、微观结构缺陷对其力学性质的影响，从而为泡沫金属的进一步的研究、开发与应用提供理论基础。     

二甲基苯酚钾作助引发剂的烯烃阴离子调节聚合

采用合成时环境友好，在四氢呋喃中溶解性良好的二甲基苯酚钾作助引发剂，正丁基锂为引发剂、二甲苯为溶剂兼作链转移剂、2G为极性调节剂对二烯烃阴离子调聚进行了研究。考察了不同D-ROK／n—BuLi对聚合物的特性粘度、分子量、分子量分布及微观结构的影响关系。制得的液体聚丁烯和聚异戊二烯可用作绿色涂料的原料。     

添加稀土对55%Al-Zn镀层的影响

通过向55％Al—Zn镀液中添加微量稀土制备了55％成—Zn热浸镀层钢板，研究了稀土对55％Al—Zn镀层的组织结构和耐盐水腐蚀性能的影响．结果表明，在镀液中加入适量(ω＝0．2％)稀土可明显提高镀层质量、细化镀层组织和提高镀层耐蚀性能，但加入过量稀土不利于耐蚀性能的提高．     

各向异性材料应力应变分析方法研究

从光弹性贴片法的基本原理出发，给出正交各向异性板内任一点的应力计算公式，提出正交各向异性板厚度效应的修正系数。对带圆孔正交各向异性板孔边应力分布做了光贴片实验并与列赫尼斯基的理论计算值进行了比较，验证了方法的正确性。     

电沉积生物活性陶瓷涂层技术

介绍了用电沉积技术 (包括电泳沉积 EPD和电化学沉积 ECD)在 Ti或 Ti合金基体上制备生物活性陶瓷涂层 HA的技术 ,评述了该技术的研究现状及发展趋势 .     

微束等离子喷涂工艺条件对Cu涂层组织和性能的影响

采用微束等离子喷涂系统在2.8-4.2kW的小功率条件下制备了Cu涂层，研究了电弧功率，工作气体流量和喷涂距离对粒子速度与涂层显微组织结构和硬度的影响。试验结果表明，电弧功率与喷涂距离对粒子速度的影响不明显，但工作气体流量对粒子速度的影响较大，电弧功率与喷涂距离对涂层的硬度影响较大，而工作气体流量对涂层的硬度影响较小。分析表明，粒子的温度对涂层硬度有较大的影响，采用微束等离子喷涂制备的Cu涂层硬度与用传统等离子喷涂设备在30kW下制备的涂层硬度相当。