淫羊藿苷含量对Mg/UMAO/CS/IC涂层性能的影响

为了研究淫羊藿苷含量对镁/超声微弧氧化/壳聚糖/淫羊藿苷（Mg/UMAO/CS/IC）涂层性能的影响,并提高纯镁的耐蚀性,采用电泳沉积（EPD）和UMAO技术在纯镁基体上制备Mg/UMAO/CS/IC涂层。采用扫描电子显微镜（SEM）、X射线衍射（XRD）、原子力显微镜（AFM）和傅立叶变换红外光谱（FTIR）对涂层的特征进行分析。对不同样品在模拟体液中进行了电化学阻抗和动电位极化的腐蚀行为研究。结果表明：当IC含量为0.4 g/L时CS/IC层具有较好的封孔效果。添加不同IC含量的Mg/UMAO/CS/IC涂层均由Mg、MgO、CS和Mg₂SiO₄组成。不同IC含量涂层的自腐蚀电流密度（i_corr）比Mg至少都低一个数量级,能为镁基底提供更有效的保护。IC含量为0.4 g/L时Mg/UMAO/CS/IC涂层的耐蚀性更好,自腐蚀电流密度（1.667×10^-6 A/cm²）最小。Mg/UMAO/CS/IC涂层可有效解决纯镁在临床骨内固定应用上降解过快的问题。     

纯镁表面负载中药提取物对复合涂层性能影响

在纯镁超声微弧氧化表面,采用电泳沉积方法引入壳聚糖作为中间层,并在壳聚糖表面浸提中药提取物。研究中药提取物对复合涂层的微观结构、磨损性能、耐蚀性和生物活性等的影响。结果表明：负载中药提取物能对超声微弧氧化表面实现封孔处理,负载中药提取物涂层具有适宜的表面状态,从而改善耐蚀性;负载中药提取物涂层为化学结合提高了涂层的结合力和抗磨损性能,并具有优异的体外生物活性。     

纯镁微弧氧化载葛根素膜层的耐蚀性和体外生物活性模拟

为了制备一种能提高医用纯Mg微弧氧化膜层的耐蚀性和生物活性的膜层,对纯Mg表面进行超声微弧氧化(Ultrasonic micro arc oxidation,UMAO),再将不同浓度的中药提取物葛根素添加到偶联剂硅烷水解液中,通过浸渍,获得载药膜层。通过SEM观察膜层表面形貌,傅里叶红外光谱分析官能团,并进行润湿角、电化学腐蚀及模拟体液浸泡试验。结果表明:载药膜层有Si-O-Si骨架和苯环官能团产生,起到了封孔的作用,复合膜层润湿角增加了48°,自腐蚀电流降低一个数量级,阻抗提高了约188 kΩ。模拟体液浸泡膜层表面有羟基磷灰石(Hydroxylapatite,HA)生成。纯Mg经UMAO,浸渍硅烷并载葛根素(1.2 mg/m L),阻抗是UMAO组的7倍,Ca/P比达到1.55,形成的复合生物膜层具有良好的耐蚀性和生物活性。     

纯钛表面载骨碎补提取物涂层的制备与性能

为了提高纯Ti的生物活性和抗感染性,采用微弧氧化(UMAO)制备多孔涂层,并以植酸(PA)偶联骨碎补提取物(ERD),并分析涂层结构、形貌及性能。结果表明,随着ERD浓度的提高,纳米颗粒增多,有PO43-,P2O74-和O=P-O-生成;载药12.5g/L的膜层摩擦磨损系数低,膜层结合力较高,为亲水涂层,膜层的电位提高了0.32V,自腐蚀电流降低一个数量级,模拟体液浸泡有羟基磷灰石(HA)生成。纯钛表面通过超声微弧氧化,植酸偶联载药的耐蚀性,结合力,生物活性均有提高。     

微弧氧化镁表面钙磷生物涂层的制备及性能

为改善镁合金的骨植性能,采用微弧氧化处理和电沉积钙磷涂层相结合的方法在纯镁表面制备具有生物活性的复合涂层,研究了复合涂层在模拟体液和细胞培养液中的组织结构演化、腐蚀行为、骨形成能力和细胞粘附行为。 微弧氧化镁表面沉积的钙磷相为二水合磷酸氢钙(DCPD)。 电沉积过程中 DCPD 优先在微弧氧化层的通孔和放电通道处形核、随后长大并覆盖微弧氧化层而起到封孔作用。 涂覆后镁的低频阻抗模值在浸泡初期超过了 10⁵ Ω·cm² ,且在 120 h 内基本保持稳定;腐蚀电流密度与纯镁相比下降了约 3 个数量级,复合涂层显著地提高了镁的耐蚀性。 复合涂层在模拟体液和细胞培养液中均表现出了诱导羟基磷灰石(HA)沉积的能力,在细胞培养液中浸泡 14 d 后涂层表面出现球状类骨 HA 组织;细胞黏附试验中,活细胞几乎黏附在整个涂层表面,表现出良好的骨形成能力和细胞活性。     

纯镁表面硅烷/透明质酸钠复合涂层的结构及腐蚀性能研究

纯镁因较快的腐蚀速率使其用于手术移植材料成为了一个障碍。为了控制其降解速率,本研究采用BTSE(1,2-(三乙氧基硅基)乙烷)硅烷化处理和共键嫁接1-(3-二甲氨基丙基)-3-乙基碳二亚胺盐酸盐(EDC)/N-羟基丁二酰亚胺(NHS)交联改性的透明质酸钠涂层的两步制备工艺在纯镁上制备复合涂层。同时使用红外光谱(FTIR)、X射线光电子能谱(XPS)、原子力显微镜(AFM)和静态接触角方法(CA)分析涂层的物化性能,通过电化学行为分析涂层在模拟体液中的耐腐蚀性能。FTIR和XPS结果表明在纯镁表面上成功的制备出复合涂层;其他结果显示,交联透明质酸钠涂层表面较裸镁、硅烷表面更平整、光滑,且呈现出亲水性,提高了其生物活性;与未改性的纯镁相比,复合涂层的腐蚀电流密度减小了2个数量级,阻抗值提高3个数量级,表现出很好的耐腐蚀性能。表明这种复合涂层作为手术移植材料在医学上具有很大的应用前景。     

沉积时间对镁合金表面Ca-P生物涂层耐蚀性能的影响

目的：镁合金在生物医学领域具有很好的应用前景,为消除其在人体环境中降解速度过快的不足,需在镁合金表面制备一层能够降低其腐蚀速度且具有很好生物相容性的防护涂层。方法采用电沉积法在AZ91D镁合金表面制备Ca-P生物涂层,沉积条件为：在Ca(NO3)2和NH4H2PO4浓度分别为0.1 mol/L和0.06 mol/L的电解液中,pH值4.5,沉积电压2 V,沉积时间分别为1、2、3和4 h。采用XRD、SEM/EDS分析Ca-P涂层的相结构、微观形貌和化学成分,测试Ca-P涂层在Hank,s模拟体液中的极化曲线。结果镁基体表面均获得物相为 DCPD(二水合磷酸氢钙)的生物涂层,但涂层表面形貌随沉积时间的不同变化明显,当沉积时间为3 h时,涂层颗粒尺寸均匀、细小,涂层钙磷比为1.324。极化曲线结果表明,沉积1 h时涂层对基体已有一定的防护作用,随着沉积时间的加长,涂层的腐蚀电压也呈增大趋势。相对镁基体,沉积3 h的涂层腐蚀电位升高了180 mV,腐蚀电流密度降低了3个数量级。结论当沉积时间为3 h时,涂层的耐蚀性最好。     

AH32钢表面等离子喷涂制备疏水涂层及其耐腐蚀性能研究

目的提高AH32海洋用钢表面的疏水性及耐蚀性,并给出最佳性能的喷涂涂层成分。方法采用大气等离子喷涂技术,在AH32钢表面制备了三种不同成分的涂层。利用微量进样器结合半球法测量了涂层的接触角,并利用Qwen-Wendt公式对涂层的表面能进行了计算,利用扫描电子显微镜观察涂层的表面形貌,利用表面粗糙度仪测量涂层的表面粗糙度,利用冲刷实验及电化学工作站测量了不同涂层的耐蚀性能,并讨论了不同涂层的疏水机制及相应的腐蚀机理。结果等离子喷涂涂层显著改善了AH32钢的疏水性能。相比而言,等离子喷涂Co基涂层及等离子喷涂Ni基涂层与水的静态接触角达到了130°以上,均具有较好的疏水效果。三种涂层均明显改善了AH32钢的耐海水冲刷腐蚀能力,其中AH32钢基体腐蚀30d后的失重为1.68×10^-2 g/cm^2,等离子喷涂Ni基涂层的腐蚀失重最小,约为4.2×10^-3 g/cm^2。极化曲线测试结果也表明,三种涂层的自腐蚀电位较基体提高了300 mV左右,并且腐蚀电流密度较基体降低了1个数量级以上,另外Co基涂层的腐蚀电流密度高于Ni基涂层的腐蚀电流密度,因此Co基涂层在腐蚀过程中表面会产生较多的羟基基团,导致其与水的静态接触角降低,最终导致其疏水性能下降。结论等离子喷涂Ni基涂层的疏水性能最好,腐蚀速率最小,耐冲刷腐蚀性能最佳,与基体相比,其腐蚀失重减小了1.26×10^-2 g/cm^2。     

LaF_3对激光原位合成TiC/Ni涂层耐蚀性的影响

以Ni60、Ti、石墨、Mo及La_3为原料,在闸板表面激光熔覆原位合成了TiC/Ni复合涂层.利用SEM、电化学腐蚀系统对涂层组织和耐蚀性能进行分析.结果表明,未添加LaF_3,和添加3%LaF_3的熔覆层中存在异质相.自腐蚀电流升高,腐蚀电位降低,耐蚀性下降;添加2%LaF_3的熔覆层中异质相消失,腐蚀电流密度降低,腐蚀电位升高,钝化区宽度增加,耐蚀性提高.     

316L表面激光熔覆复合微弧氧化制备陶瓷涂层

目的提高316L不锈钢表面的耐蚀性和生物活性。方法首先采用激光熔覆技术在316L不锈钢表面制备钛层,然后对钛层表面进行微弧氧化处理,从而在316L不锈钢表面制备出含有Ca、P元素的多孔状陶瓷涂层。利用扫描电子显微镜(Scanning Electron Microscope,SEM)、能谱仪(Energy Dispersive Spectrometer,EDS)、X射线衍射仪(X-Ray Diffraction,XRD)分析了钛层厚度对陶瓷涂层的表面显微形貌、元素含量及物相组成的影响。利用电化学实验、浸泡实验分别测试了涂层在1.5倍SBF溶液中的耐蚀性能和生物活性。结果通过激光熔覆复合微弧氧化能够在316L不锈钢表面制备出多孔状陶瓷涂层。随着钛层厚度的增加,微弧氧化原位生成的陶瓷涂层致密度、厚度也增加。当钛层厚度达到0.4 mm时,微弧氧化后得到的陶瓷涂层完整致密,厚度达到20μm。涂层主要由锐钛矿相Ti O2、金红石相Ti O2组成。极化曲线分析可知,腐蚀电位Ecorr为-0.162 V,腐蚀电流密度降至5.11×10-7 A/cm2。陶瓷涂层在1.5倍SBF中浸泡3天后表面即有羟基磷灰石沉积。结论通过激光熔覆复合微弧氧化在316L不锈钢表面制备的陶瓷涂层在模拟体液环境下具有较好的耐蚀性能,同时也具备良好的生物活性。     

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 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.     

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.     

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.     

Formulas of Tension of Continuous Rolling Process

The development of computer controlled continuous rolling process calls for a mathematical expression that can express the inequality condition of "constant flow". Tension is the link of the continuous rolling process. From the condition of dynamic equilibrium, a differential equation of tension is given out. On the basis of the physical rules established from the industrial practice and experimental studies, the law of volume constancy, the linear relation of forward slip and tension, the state equation of continuous rolling, the formula of dynamic tension, and the formula of static tension have been obtained. These formulae reflect the functional relations between tensions, thickness, roll velocity, and time in the continuous rolling process. It is implied that the continuous rolling process is a gradually steady, controllable, and measurable dynamic system. An assumption of predicting the thickness of a steel plate using these tension formulae is also put forward.