稀土对两种青铜的铸态组织和某些性能影响的研究

研究了不同稀土对７－１３－４－１铝青铜（无镍高锰铝青铜）产ＺＣｕＰｂ６Ｓｉ３Ｍｎ（含铅硅青铜）的铸态组织、流动性、耐磨性和耐蚀性的影响。结果表明，适量稀土可以细化合金的铸态组织，大大改善合金中铅的偏析；两种合金的标准螺旋形式样长度分别增加１０７－１１２％和４５－８５％，靡损量分别－７０％和３８－５５％，腐蚀量分别减少４０－５０％和３５－５０％；并探讨了出现这种变化规律的原因。     

新型铝青铜Cu-14Al-X的热处理强化

试制了一种含铝量高于铜铝二元合金共析点（11.8wt%）的耐磨铝青铜,研究了合金经过不同热处理后的组织和性能.结果表明,经920 ℃固溶处理及580 ℃时效后的合金具有优良的综合力学性能.合金强化是由于先析出第二相γ2的分布逐渐由连续网状转变为离散状,κ相质点的形状由尖变圆、粗大变得细小,并脱离网状硬脆相γ2的包围,镶嵌于强度和硬度综合性能较佳的β＋α基体相中.     

新型弹性材料-QSn_(4-1-0.04)锡铁磷青铜

QSn（4－1－0.04）锡铁磷青铜是一种新型弹性材料，在许多工业领域可取代QSn（6.5－0.1）锡磷青铜，所开发合金的物理、力学性能均达到或超过QSn（6.5－0．1）锡磷青铜，导电率提高了40％，可节约Sn2％，能耗省、成本低。     

一种多元铝青铜合金的摩擦磨损特性

用适量Fe、Ni、Mn、Co、Be、Zn元素制备了一种多元铝青铜耐磨合金,用XRD、SEM等对试验合金的铸态和固溶时效状态下的组织进行了观察和比较,并在MMW-1型万能磨损试验机上对合金在干摩擦和油润滑条件下进行了摩擦磨损试验。结果表明,多元铝青铜合金热处理态（960℃×2 h固溶＋520℃×3 h时效）的显微组织由β＇、γ2和κ相组成,其摩擦因数低于铸态,油润滑条件下具有良好的耐磨损性能。     

热处理对新型铝镍青铜组织与性能的影响

采用合金化方法研制了一种新型铝镍青铜模具材料,并利用金相显微镜、XRD、布氏硬度计等研究了热处理对其组织与性能的影响。结果表明,新型铝镍青铜铸态组织主要由α相、β'相、γ_2相和κ相组成,经940℃×2 h固溶+500℃×4 h时效的最佳热处理工艺处理后,合金的硬度为380 HBW,抗拉强度为837 MPa,伸长率为9.3%,热扩散系数为16.6 mm~2/s,表现出优异的综合性能。     

Ti—Al—W—Zr系合金的相转变和机械性能的关系

研究了两类四元系Ｔｉ－Ａｌ－Ｗ－Ｚｒ合金，一类是含钨量（６％）和含锆量（３％）不变，而铝浓度可变（０～２０％）；二类是锆含量（３％）和铝含量（６％）不变，而钨含量改变（０～２０％）． 采用碘化钛、碘化锆、Ａ９９９铝和Ｔｉ－２５％Ｗ中间合金，用非自耗电弧熔炼后再悬浮熔炼的方法制做了合金铸锭．合金锭在真空石英管中按以下制度进行热处理（均匀化）：１１５０℃、１００ｈ→１１００℃、 １２５ｈ→ １０００℃、１５０ｈ→９００℃、４００ｈ→８００℃，８００ｈ→６５０℃， ２ ５００ｈ→空气．在６００℃退火后（即…     

EFFECT OF Cr ON MICROSTRUCTURE OF Ti_3Al＋TiAl ALLOYS

研究了Ｔｉ－４４．９Ａｌ（ａｔ．－％）和Ｔｉ－４４．３Ａｌ－３Ｃｒ（ａｔ．－％）合金的铸态组织及其在热处理过程中的变化。结果表明：Ｃｒ增加了Ｔｉ－Ａｌ合金中ＴｉＡｌ（γ）相的含量，促使Ｔｉ３Ａｌ（α２）相由片状变成块状；加速了α２＋γ片状组织的不连续粗化过程，形成了尺寸较小的新生α２＋γ晶。因此，加Ｃｒ和１１５０℃长时热处理是细化α２＋γ两相合金铸态粗晶组织的有效途径；Ｃｒ促进有序体心立方β２相的     

CuZnAl(RE)形状记忆合金干滑动磨损性能研究

采用不同热处理工艺、不同栽荷、不同磨损时间，对2种成分（不同相变点）的CuZnAl（RE）形状记忆合金进行了干滑动磨损试验，与锡青铜和铝铁青铜做了对比试验，用电子扫描显微镜和x射线衍射仪对磨损表面及合金相组成进行了观察和检测。试验结果表明，晶粒细化与锻打能提高合金的耐磨性，合金的M相比β相耐磨，两级时效处理的合金耐磨性能优于分级淬火处理的合金，CuZnAl（RE）形状记忆合金的耐磨性优于锡青铜和铝铁青铜；CuZnAl（RE）形状记忆合金耐磨的原因主要在于，形状记忆效应和超弹性、应力诱发马氏体相变、晶粒细化等。     

THS—HL2铅基钎料的研制与应用

随着一种高耐磨耗铝青铜合金在日本等国的开发与应用，由该材料制成的冲压模已经在天津微型汽车厂使用。对此类大型模具的维修，迫切需要一种新型的补焊材料，THS－HL2铅基钎料的研制与开发便应运而生。它的研制成功，填补了我国此种铜基钎焊料的空白。     

THS－ HL2铜基钎料的研制与应用

随着一种高耐磨耗铝青铜合金在日本等国的开发与应用，由该材料制成的冲压模已经在天津微型汽车厂使用。对此类大型模具的维修，迫切需要一种新型的补焊材料， THS－ HL2铜基钎料的研制与开发便应运而生。它的研制成功，填补了我国此种铜基钎焊料的空白。     

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.     

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.     

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.     

RHEOLOGY FEATURE OF SIMPLE METAL MELT

The rheology feature of Sb, Bi melt and alloys was studied using coaxial cylinder high-temperature viscometer. The results showed that the curve of torsion-rotational speed for Sb melt presents a linear relation in all measured temperature ranges, whereas for the Bi melt, the curve presents obvious non-Newtonian feature within the low temperature range and at relative high shear stress. The rheology feature of Sb80Bi20 and Sb20Bi80 alloy melts was well correlated with that of Sb and Bi, respectively. It is considered that the rheology behavior of Sb melt plays a crucial role in Sb80Bi20 alloy and that of Bi melt plays a crucial role in Sb20Bi80 alloy.     

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.