Size Effect of Thermal Stability of Zr47Ti12.9Cu11Ni9.6 -Be16.7Nb2.8 Metallic Glass

采用真空铜模吸铸和单辊真空薄带技术制备出直径5 mm的Zr47Ti12.9Cu11Ni9.6Be16.7Nb2.8金属玻璃棒材和相同成分厚30μm的金属玻璃薄带。利用热分析技术和Kissinger方法分析计算了不同尺寸金属玻璃的热稳定性参数,主要包括:玻璃转变温度Tg,晶化温度Tx,玻璃转变和晶化激活能Eg、Ex等。结果表明:Zr47Ti12.9Cu11Ni9.6Be16.7Nb2.8金属玻璃在热稳定性上表现出"越小越稳定"的特征,薄带的热稳定性参数均高于棒材,表现出更好的热稳定性。不同尺寸Zr47Ti12.9Cu11Ni9.6Be16.7Nb2.8金属玻璃的晶化行为进一步验证了这一特征:在晶化温度远低于金属玻璃薄带情况下,棒材却更易晶化,晶化过程中获得了比金属玻璃薄带更加完整的晶化组织。     

钨丝增强(Zr41.2Ti13.8Cu12.5Ni10Be22.5)100-xNbx非晶复合材料的力学性能

采用XRD、SEM等表征方法研究钨丝增强(Zr41.2Ti13.8Cu12.5Ni10Be22.5)100-xNbx非晶复合材料的力学行为.研究表明,分别加入x=1,3,5,7(atA)的Nb后,制备的复合材料试样基体仍为非晶态:随Nb含量的增加,钨丝增强(Zr41.2Ti13.8Cu12.5Ni10Be22.5)10...     

氢对Zr41.2 Ti13.8 Cu12.5 Ni10 Be22.5 大块非晶合金晶化特性的影响

利用电弧熔炼及铜模快速铸造的方法制备Zr41.2Ti13.8Cu12．5Ni10Be22．5大块非晶合金，通过电解丙三醇和磷酸的电化学法向大块非晶中充入氢。测试了大块非晶态合金中充入氢的含量及体积变化规律，采用XRD，DSC技术研究了氢对大块非晶的晶化特征的影响。结果表明：Zr41．2Ti13．8Cu12．5Ni10Be22．5大块非晶可充入的氢与金属的摩尔比为0．92，体积膨胀3．5％；随着氢含量的增加，玻璃转变温度和晶化温度稍有提高，并使结晶过程不同阶段的放热峰变弱。     

含钴锆基块状非晶合金的制备与力学性能

采用水淬法制备了Zr—Ti—Cu—Ni—Be—Co块状非晶合金(BMGs)。使用XRD进行相分析，采用热分析仪进行玻璃转变温度、晶化温度和热稳定性等的测定，用SEM观察试样压缩后的外表面和断口形貌。研究了Co对Zr—Ti—Cu—Ni—Be合金非晶形成能力(GFA)、热稳定性及力学性能的影响。结果表明：含Co的所有Zr—Ti—Cu—Ni—Be BMGs都有1个明显的玻璃转变点和宽的过冷液相区(△T）。Zr38Ti17Cu10.5Co12Be22.5合金具有和Zr41Ti14Cu12.5Ni10Be22.5合金相当的△T；Co的添加明显提高Zr—Ti—Cu—Ni—Be BMGs的力学性能，含Co量大于10at％的Zr—Ti—Cu—Ni—Be BMGs的压缩断裂强度（σf）超过2000MPa，Zr38Ti17Co22.5Be22.5合金的σf达到2230MPa，比Zr41Ti14Cu12.5Ni10Be22.5合金的σf提高23％。     

Zr41．25Ti13．75Ni10Cu12．5Be22．5熔体与W的润湿及复合

用座滴法研究了高真空下Zr41.25Tin13.75Ni10Cu12.5Be22.5（原子百分数，下同）熔体在W上的润湿行为及界面相互作用，并用浸渗法制备了W丝增强的Zr41．25Ti13．75Ni10Cu12.5Be22.5块状非晶复合材料。结果表明：在1053K～1173K之间，Zr41.25Ti13.75Ni10Cu12.5Be22.5熔体与W具有较好的润湿性。润湿温度升高会显著降低平衡接触角，并加速熔体的铺展，但也会增大W的溶解量。继续升高温度对平衡接触角和达到平衡接触角所需时间的影响很小。好的润湿性和快的铺展速率为制备W丝增强的Zr41.25Ti13.75Ni10Cu12.5Be22.5块状非晶复合材料选择合理的工艺参数提供了较大的自由空间。     

定向凝固制备内生晶体增塑的锆基非晶复合材料

通过Bridgman定向凝固成功制备了成分为Zr58.8Ti14.3Nb5.2Cu6.1Ni4.9Be1.0的内生枝晶增塑的非晶复合材料.内生枝晶的尺寸和体积分数可以经抽拉速度的改变得以控制,进而实现了对其力学性能的调节.研究表明,枝晶的大小与抽拉速度呈线性关系,体现出定向凝同在制备非晶复合材料方面可调控析出相的优势.通过对实验参数抽拉速度的优化得出,当抽拉速度为1.0 mm/s时,最高压缩强度达到了1930 MPa,断裂塑性达到11.3%.     

Wf／ZrTiCuNiBe非晶合金复合材料的界面特征与性能

用渗流铸造水淬法制备了φ6mm×50mm的W纤维增强的Zr4125Ti13．75Cu12.5Ni10Be22.5非晶合金复合材料。采用扫描电镜（SEM）分析了相同渗流时间，不同渗流温度复合材料的界面反应形貌，并采用Push-out法测定了界面剪切强度，讨论了界面特征、界面剪切强度与宏观压缩断裂行为之间的关系。结果表明：渗流铸造法制备的W纤维增强Zr41.25Ti13．75Cu12.5Ni10Be22.5非晶合金复合材料明显提高了非晶合金的塑性和断裂强度。复合材料界面结合包括界面扩散和界面反应两个过程。界面反应程度加剧时界面剪切强度增大，复合材料的破坏方式由纵向劈裂转变为剪切破坏。     

冷却速率和高径比对钛基非晶复合材料力学性能的影响

通过制备不同尺寸的Ti45.7Zr33Ni2.9Cu5.9Be12.5非晶复合材料样品,研究了冷却速率和高径比对内生枝晶相增强钛基非晶复合材料力学性能的影响.随着制备过程中冷却速率的降低,非晶复合材料中枝晶相的尺寸逐渐增大,同时枝晶相熟化的现象也趋于明显.在力学性能方面表现为非晶复合材料的强度降低而塑性增强.与以往非晶复合材料性能对高径比比较敏感所不同的是,本工作中的Ti45.7Zr33Ni2.9Cu5.9Be12.5非晶复合材料的力学性能对高径比的变化并不敏感,原因在于晶态相的存在以及其中的形变诱发马氏体相变行为的发生对非晶复合材料内部应力分布的调节.     

镍基非晶合金涂层的制备与腐蚀性能

用气体雾化法制备了Ni53Nb20Ti10Zr6Co6Cu3非晶合金粉末,将粒度小于25μm的非晶粉末用动力金属喷涂工艺制备了非晶涂层．研究表明,非晶涂层厚度约500μm,涂层的空隙率随喷涂温度和沉积率的增加而减少．涂层腐蚀性能的评价选用1kmol／m^3 HCl水溶液,动电位极化曲线测量表明,随着空隙率的减少,涂层呈现出与非晶合金相当的优良耐蚀性能．     

Sn对Ti-Zr-Cu-Ni系非晶薄带热稳定性及耐蚀性能的影响

通过单辊甩带法制备了Ti40Cu39Zr10Ni11-xSnx(x=0,3,7,11)非晶薄带。运用X射线衍射仪(XRD)、差示扫描量热仪(DSC)、电化学工作站、扫描电镜(SEM)等手段测试了合金的组织与性能特性,研究了Sn替换Ni对合金热稳定性及生物耐蚀性能的影响。结果表明,随着Sn的添加,Ti40Cu39Zr10Ni11-xSnx(x=0,3,7,11)合金试样均表现为完全的非晶结构。与Ti40Cu39Zr10Ni11非晶合金相比,Ti40Cu39Zr10Sn11非晶合金的热稳定性稍有改善,且生物耐蚀性能得到明显提高。因此,不含Be、Ni等对人体有害元素的Ti40Cu39Zr10Sn11非晶合金具有作为生物医用材料的潜力。     

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.