Ni对C—B4C—SiC复合材料显微结构与性能的影响

本文研究了烧结助剂Ｎｉ对Ｃ－Ｂ４Ｃ－ＳｉＣ复合材料显微结构与性能的影响。Ｘ射线衍射表明Ｎｉ在烧结温度下与ＳｉＣ、Ｂ４Ｃ发生反应在晶界生成Ｎｉ４．６Ｓｉ２Ｂ，并产生液相，有效地促进了Ｃ－Ｂ４Ｃ－ＳｉＣ复合材料的烧结，抑制了晶粒的长大，使复合材料密度与强度大幅度地增加，电阻率下降；同时Ｎｉ４．６Ｓｉ２Ｂ在氧化时生成致密的２ＮｉＯ．Ｂ２Ｏ３，包裹了易氧化的Ｂ４Ｃ和Ｃ，有效地防止了复合材料的氧化，从而大大     

Ni对C－B_4C－SiC复合材料显微结构与性能的影响

本文研究了烧结助剂Ｎｉ对Ｃ－Ｂ_４Ｃ－ＳｉＣ复合材料显微结构与性能的影响．Ｘ射线衍射表明Ｎｉ在烧结温度下与ＳｉＣ，Ｂ_４Ｃ人发生反应在晶界生成Ｎｉ_（４．６）Ｓｉ_２Ｂ，并产生液相，有效地促进了Ｃ－Ｂ_４Ｃ－ＳｉＣ复合材料的烧结，抑制了晶粒的长大，使复合材料密度与强度大幅度地增加，电阻率下降；同时Ｎｉ_（４．６）Ｓｉ_２Ｂ在氧化时生成致密的２ＮｉＯ·Ｂ_２Ｏ_３，包裹了易氧化的Ｂ_４Ｃ和Ｃ，有效地防止了复合材料的氧化，从而大大提高了制品的抗氧化性能．     

化学复合镀制备高活性节能NiCo2O4电极

在贱金属铁基表面化学镀Ｎｉ－Ｃｏ－Ｐ,然后通过化学复合镀制得Ｎｉ－Ｃｏ－Ｐ－Ａ１２Ｏ３底层,复合镀层用ＮａＯＨ溶液浸出,可制得新型Ｎｉ－Ｃｏ－Ｐ微孔活性中间导参中间导地涂覆匹配性较好的ＮｉＣｏ２Ｏ４表面活性层,该表面活性层由一定浓度配比的Ｎｉ（ＮＯ３）２和Ｃｏ（ＮＯ３）２通过高温热解而成。 射结果表明表面活性层是由ＮｉＣｏ２Ｏ４组成,不存在ＮｉＯ和Ｃｏ３Ｏ４的独立相。这种新型表面活性层用于碱性水电     

氧化物薄膜促使镍铬合金高温选择氧化的研究

表面沉积Ｙ２Ｏ３薄膜可以促使Ｎｉ－１５％Ｃｒ合金在１０００℃中生成Ｃｒ２Ｏ３选择性氧化膜，氧化量下降约２０倍，而沉积Ａｌ２Ｏ３薄膜仅在较短的时间内使合金的局部表面生成Ｃｒ２Ｏ３选择性氧化膜。从沉积氧化物薄膜对Ｃｒ２Ｏ３氧化膜的生核及生长过程的作用，对氧扩散的阻挡作用，以及氧化物薄膜与Ｃｒ２Ｏ３氧化膜掺杂后引起氧化膜中传质过程和应力状态的变化，分析了氧化物薄膜促使镍铬合金在较低铬含量下发生高温选择氧     

稀土氧化物改进高温涂层的氧化行为研究

研究了几种含或不含ＣｅＯ２的ＮｉＡｌ基涂层在９００及１０００℃下的高温氧化行为，并对氧化前的涂层组织，氧化膜形貌及氧化膜／基体界面结构等进行了观察，从而就ＣｅＯ２对Ａｌ２Ｏ３膜的氧化动力学和ＮｉＡｌ组织退化的影响探讨了ＣｅＯ２改善涂层抗高温氧化性能的机制。     

稀土和铝合金化对25Cr2Ni4WA钢穿孔顶头抗氧化性能的影响

试验研究了穿孔顶头常用钢２５Ｃｒ２Ｎｉ４ＷＡ钢经Ｒｅ（稀土）和Ｒｅ（稀土）＋Ａｌ两种合金化工艺后的抗氧化性能，主要包括氧化膜形貌、相组成、与基体结构强度等。试验结果与分析表明，Ｒｅ＋Ａｌ合金化后穿孔顶头表面状况有很大改善，高温下生成的表面氧化膜主要由Ａｌ２Ｏ３和Ｃｒ２Ｏ３Ｏ组成，且与基体结合良好，从而可改善穿孔顶头塌鼻、粘钢现象；单一Ｒｅ合金化对表面氧化膜也有一定改善，但效果不如Ｒｅ＋Ａｌ合金化的     

Ni42Cr6Fe合金在高温湿氢中的氧化膜组织结构及生长过程研究

用ＴＥＭ、Ｘ射线衍射、ＳＥＭ等技术研究了Ｎｉ４２Ｃｒ６Ｆｅ玻封合金在高温湿氢中的氧化膜生长过程。氧化初期，Ｃｒ＿（２）Ｏ＿３和尖晶石氧化物同时形核长大，前者在晶界处形核长大，后者在晶内处形核长大。随后由于Ｃｒ的选择氧化，氧化膜主要以Ｃｒ２Ｏ３生长为主．当氧化进行到一定程度后，由于表面层Ｃｒ的贫化，氧化膜生长转化以（Ｆｅ，Ｍｎ）Ｃｒ２Ｏ４尖晶石氧化物生长为主．最后形成表层以粗大晶粒（Ｆｅ，Ｍｎ）Ｃｒ２Ｏ４为主，底部以较小晶粒Ｃｒ２Ｏ３为主，中部由大晶粒（Ｆｅ，Ｍｎ）Ｃｒ２Ｏ４围绕小晶粒Ｃｒ２Ｏ３的稳态氧化膜组成     

渗铝涂层对Ni_3Al－Mo基合金高温氧化的防护作用及机理

采用高活度渗铝工艺在ＩＣ－６（Ｎｉ３Ａｌ－Ｍｏ基）合金表面获得内扩散型渗铝涂层，在氮气环境下对渗铝涂层进行扩散处理．利用光学显微镜、ＳＥＭ、ＥＰＭＡ、ＸＲＤ分析研究了涂层的成分及组织结构，测定表明，涂层中的钼以Ｍｏ３Ａｌ沉淀相的形式存在．等温氧化及循环氧化实验表明，渗铝涂层的抗高温氧化性能明显优于ＩＣ－６合金；保护性的Ａｌ２Ｏ３氧化膜阻止了钼的氧化物的形成，避免了ＩＣ－６合金在循环氧化中出现的ＮｉＭｏＯ４相的多晶型转变，显著改变了合金的抗循环氧化能力；涂层经１０００℃、３００ｈ等温氧化及１０００℃、１００ｈ循环氧化后，未出现β－ＮｉＡｌ相的分解，可认为涂层具有较强的保护作用。     

溅射Ni-8Cr-3.5Al纳米晶涂层的抗高温氧化行为

对Ｎｉ－８Ｃｒ－３．５Ａｌ质量分数,％合金及其纳米晶涂层进行了１０００℃空气中高温氧化研究。结果表明：Ｎｉ－８Ｃｒ－３．５Ａｌ纳米晶涂层的抗高温氧化性能优于Ｎｉ－８Ｃｒ－３．５Ａｌ合金。这主要在于Ｎｉ－８Ｃｒ－３．５Ａｌ纳变涂层表面生成了具有分层结构含一连续α－Ａｌ２Ｏ３内层的氧化膜,而Ｎｉ－８Ｃｒ－３．５Ａｌ合金则生成了由Ｃｒ２Ｏ３内氧化物组成的氧化膜。讨论了涂层氧化膜的生成过程。     

溅射Ni—Cr—Al—Ti涂层高温氧化过程中组织变化对生成TiO …

观察了溅射Ｎｉ－９．７Ｃｒ－５．５Ａｌ－７Ｔｉ（质量分数）纳米晶涂 高温氧化过程中的组织变化,探讨了溅射涂层表面氧化膜以及涂层预氧化９０ｍｉｎ后磨去生成的氧经膜再重新氧化生成氧化膜中ＴｉＯ２的生长,认为溅射涂经过程中Ｎｉ３（ＡｌＴｉ）相的析出与ＴｉＯ２的生成长大有着密切关系,对两种不同民政部下Ｎｉ３（ＡｌＴｉ）相对ＴｉＯ２生长的影响机制进行了分析。     

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.