高耐腐蚀性能FeCoCrMoCBY合金中的最优Cr/Mo摩尔比（英文）

采用水冷铜模吸铸法制备(Fe_(41)Co_7Cr_(15)Mo_(14)C_(15)B_6Y_2)_(100-x)Cr_x(x=0,4,8,12,摩尔分数,%)块体金属玻璃,利用电化学方法研究其在1 mol/L HCl中的耐腐蚀性能。电化学测试发现钝化电流密度降低了大约一个数量级,同时发现适当的Cr/Mo摩尔比可以保证钝化膜的稳定性。Mott–Schottky曲线证实当Cr/Mo摩尔比为1.37~1.69时,合金的钝化膜更致密。采用XPS分析钝化膜中元素的化学状态,发现合金耐腐蚀性能与Cr/Mo摩尔比有关,钝化膜的稳定性由Cr和Mo协同作用决定。钝化膜的主要成分为Cr~(3+)的氧化物。当电位高于0.5 V(vs SCE)时,Mo6+是决定钝化膜稳定性的主要因素。适当的Cr/Mo摩尔比可以降低钝化膜的腐蚀速率。     

聚苯胺/不锈钢双极板在H2SO4中腐蚀性能的变化规律

目的提高质子交换膜燃料电池(PEMFC)双极板的耐蚀性。方法采用循环伏安法,在316L不锈钢(SS)表面电合成导电聚苯胺(PANI)膜,制备PANI/316L SS复合双极板。用红外光谱确定PANI官能团结构,用扫描电镜观察表面形貌,用X射线光电子能谱研究PANI膜成分和键合状态。用0.2 mol/L H2SO4模拟PEMFC腐蚀环境,采用极化曲线研究PANI/316LSS耐腐蚀性能,采用开路电位(OCP)和电化学阻抗谱(EIS),研究PANI/316L SS在长期浸泡过程中的腐蚀行为的变化规律。结果 PANI膜具有中间氧化态结构,呈现纤维堆积形貌。XPS结果表明,PANI膜中含有C、N、S和O等元素,聚合过程中"对阴离子"SO42-通过"掺杂"进入PANI分子链。涂覆PANI薄膜的316L SS腐蚀电位提高了0.17 V,长期浸泡过程中,OCP介于0.19～0.32 V之间,说明PANI/316L SS的腐蚀倾向降低。浸泡初期,OCP增大对应于膜/基界面处钝化膜的形成;浸泡中期,OCP下降/上升与钝化膜的溶解/修复有关;浸泡后期,OCP持续下降源于钝化膜的溶解。EIS的Nyquist图由高频端容抗弧和低频端扩散尾构成。结论随着浸泡时间延长,PANI膜被氧化,导致"对阴离子"SO_4~(2-)从PANI中发生"脱掺杂",使膜电阻增加,容抗弧半径增大。浸泡82天,PANI/316L SS体系仍具有良好的耐腐蚀性能。     

低温恒电流氮化提高316L不锈钢导电及耐腐蚀性能

目的 解决恒电位电化学氮化时高的过电位引起的析氢反应对316LSS综合性能的恶化,提出采用恒电流技术对其进行电化学氮化改性,并确定最佳的试验参数.方法 借助于循环伏安、计时电位,交流阻抗和动电位极化等电化学方法,扫描电镜及X射线光电子能谱分析,研究还原电流密度对316LSS表面形貌、耐腐蚀性能、疏水性能和接触电阻等的影...     

电位对聚苯胺/不锈钢双极板腐蚀性能的影响

目的 增强双极板在质子交换膜燃料电池(PEMFC)工作条件下的耐腐蚀性能.方法 以1-乙基-3-甲基咪唑硫酸乙酯(EMIES)离子液体作为聚合反应电解质,采用循环伏安法在316L不锈钢(SS)上电聚合聚苯胺(PANI)薄膜制备PANI/316L SS双极板.采用SEM观察表面形貌,采用FTIR分析官能团结构,采用XPS分析元素组成和键合状态.采用恒电位法控制PANI/316L SS电位分别为0.5、0.6、0.7 V(vs.SCE)以模拟PEMFC阴极电位,测量恒电位极化后开路电位、极化曲线和电化学阻抗谱(EIS)的变化.结果 PANI膜均匀平整局部有微裂纹.FTIR显示有苯环、醌环、S=O和—COOH伸缩振动.XPS表明PANI膜含有C、N、O和S等元素.PANI/316L SS极化曲线在钝化区内电流密度波动较大,EIS的Nyquist图由高频容抗弧和低频直线构成,容抗弧半径随着极化电位的升高而增大.结论 PANI为中间氧化态结构,EMIES阴离子(CH3CH2SO4–)和草酸阴离子(HOOC-COO–)在PANI分子链中均有掺杂.在PEMFC阴极工作电位下PANI/316L SS处于阳极极化状态,电位对PANI/316L SS的耐蚀性影响显著,在0.6 V下PANI/316L SS呈现很好的耐蚀性,电位升高至0.7 V时,发生PANI过度氧化,导致"对阴离子"脱掺杂,使PANI/316L SS的导电性和耐蚀性下降.     

聚苯胺膜/不锈钢复合双极板的耐蚀性和导电性

目的在316L不锈钢(SS)表面沉积聚苯胺(PANI)薄膜,制备PANI/316L SS复合材料双极板,提高316LSS在质子交换膜燃料电池工作环境下的耐腐蚀性能和导电性能。方法采用循环伏安法,在0.1 mol/L苯胺单体与0.2 mol/L H2SO4组成的水溶液中,在316L SS基体上电化学聚合PANI薄膜。采用SEM观察表面形貌,采用FTIR和Raman分析PANI官能团结构,采用XPS分析PANI膜中元素组成和化学键合状态。采用开路电位(OCP)、极化曲线和电化学阻抗谱(EIS)研究PANI/316L SS腐蚀性能。采用四探针技术研究PANI膜的导电性。结果 SEM观察显示PANI膜为纤维状堆积物。红外光谱发现苯环、醌环和S==O伸缩振动,拉曼光谱发现掺杂态的半醌自由基C—N+·,确定合成的PANI具有中间氧化态结构。XPS分析表明,聚合过程发生了质子酸掺杂,"对阴离子"(SO42-)进入PANI分子链中,掺杂度为3%～4%。电化学测试表明,PANI/316L SS的OCP为0.15～0.25 V,PANI使316L SS腐蚀倾向降低,随着Cl-浓度的升高,腐蚀电流密度增大。结论在酸性含Cl-介质中,PANI/316L SS体系耐蚀性好,膜/基界面处保护性氧化膜Fe2O3和Cr2O3的形成,使PANI/316L SS体系耐腐蚀性能提高。在制备条件下,PANI膜厚度介于146～315μm之间,电导率范围为1.33～8.91 S/cm。     

稀土铈对Fe-3Cr钝化膜电化学腐蚀行为的影响

利用电容测试法和电化学阻抗谱技术研究了稀土Ce对Fe-3Cr合金在1 mol/L NaHCO3+0.5 mol/L Na2CO3缓冲溶液中所形成的钝化膜电化学腐蚀行为的影响.结果表明:稀土Ce能大大降低钝化膜内的施主密度,使膜电阻和离子在膜内的传递电阻增大,导致离子在膜内的扩散能力降低.稀土的加入可以增强基体合金在含有Cl-缓冲溶液中的耐腐蚀性能.     

316L和HR-2不锈钢在盐酸液膜环境中的钝化与点蚀

基于自行设计组装的盐酸液膜腐蚀模拟装置,采用腐蚀挂片、电阻探针、Tafel极化、电化学阻抗等方法,研究了316L和HR-2不锈钢在浓度分别为1、0.5和0.1 mol/L,温度分别为90、70和60℃的盐酸蒸汽环境中的钝化和点蚀行为,并利用金相显微镜、XRD对腐蚀试样和腐蚀产物进行了分析。结果表明:两种不锈钢的腐蚀速率随时间先加快后减慢最后趋于稳定,316L不锈钢的腐蚀速率相对较高;两种不锈钢均能形成稳定钝化区,且维钝电流密度相差不大,HR-2孔蚀电位的钝化区间总体都比316L不锈钢高,说明HR-2不锈钢更耐腐蚀;另外,两种不锈钢表面腐蚀产物成分基本相同,316L不锈钢表面的腐蚀产物更多更密集,这是由于O的吸附被C1-所取代,钢体表面上的钝化膜难以形成或破坏,并且更可能导致不锈钢点蚀。     

成膜电位对316L不锈钢在硼酸溶液中电化学行为的影响

采用动电位极化和电化学阻抗方法研究了316L不锈钢在硼酸溶液中钝化膜的电化学性能,并通过MottSchottky曲线考察了不同成膜电位下钝化膜的半导体性质。结果表明,316L不锈钢在-0.1~0.5 V发生了明显的钝化现象,在0.3 V成膜电位下形成的钝化膜更加致密和稳定。Mott-Schottky曲线结果表明,成膜电位对于316L不锈钢钝化膜的半导体特征性质没有根本影响,在钝化区间内钝化膜呈p型半导体特征,在0.3 V时受主密度最小。     

Hank‘s人工模拟体液中离子注氮对4种植入金属材料腐蚀行为的影响

采用电化学测试技术研究了离子注氮对SUS316L不锈钢，Co-Cr合金，工业纯钛和Ti-6Al-4V植入合金在Hank’s人工模拟体液中腐蚀行为的影响。腐蚀电位和极化曲线的测量结果表明，注氮使4种植入金属材料的腐蚀电位正移，钝化电位区间扩大，耐蚀性明显提高。注氮的工业纯钛和Ti-6Al-4V合金的耐蚀性最佳，其钝化区拓宽为4V以上。通过AES分析发现，离子注氮后钛及其合金表面形成的氮化钛膜层及弥散的氮化钛析出相的化学效应，使基体电化学性能得到提高。注氮的Co-Cr合金的耐蚀性略优于SUS316L不锈钢。Co-Cr合金表面形成的钴氮化合物相对基体起到保护作用，降低了腐蚀速率。SUS316L不锈钢表面形成铁和铬氮化合物膜，有效地阻止了Cr^3 的水解，且氮离子注入促进Fe3O4的产生，提高了耐腐蚀性能。     

309不锈钢纳米涂层在酸性溶液中的电化学腐蚀行为

用动电位极化、恒电位极化及交流阻抗技术研究了 309 不锈钢及其溅射纳米涂层在 0.25 mol/L Na2SO4 0.05 mol/L H2SO4 和 0.5 mol/L Nacl 0.05 mol/L H2SO4溶液中的电化学腐蚀行为.结果表明,在 0.25 mol/L Na2SO4 0.05 mol/L H2SO4 溶液中,纳米涂层和不锈钢形成的钝化膜的抗腐蚀能力差别较小;而在 0.5 mol/L NaCl 0.05mol/L H2SO4 溶液中,纳米涂层的耐点蚀性能有了很大提高,这是由于纳米化使涂层表面形成的钝化膜更加致密、更加稳定;同时,通过容抗测量研究了纳米涂层和不锈钢钝化膜的电子结构,并提出了相应的腐蚀机制.     

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.     

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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Antimony Induced Crystallization of Amorphous Silicon

Antimony induced crystallization of PVD (physics vapor deposition) amorphous silicon can be observed on sapphire substrates. Very large crystalline regions up to several tens of micrometers can be formed. The Si diffraction patterns of the area of crystallization can be observed with TEM (transmission electron microscopy). Only a few and much smaller crystals of the order of 1μm were formed when the antimony layer was deposited by MBE (molecular beam epitaxy) compared with a layer formed by thermal evaporation. The use of high vacuum is essential in order to observe any Sb induced crystallization at all. In addition it is necessary to take measures to limit the evaporation of the antimony.     

A CUMULATIVE FATIGUE DAMAGE RULE UNDER THE ALTERNATIVE OF CORROSION OR CYCLIC LOADING

Fatigue damage increases with the applied loading cycles in a cumulative manner and the material deteriorates with the corrosion time. A cumulative fatigue damage rule under the alternative of corrosion or cyclic loading was proposed. The specimens of aluminum alloy LY12-CZ soaked in corrosive liquid for different times were tested under the constant amplitude cyclic loading to obtain S-N curves. The test was carried out to verify the proposed cumulative fatigue damage rule under the different combinations among corrosion time, loading level, and the cycle numbers. It was shown that the predicted residual fatigue lives showed a good agreement with the experimental results and the proposed rule was simple and can be easily adopted.