ZaAl40合金过饱和固溶体时效特性

采用Ｘ射线衍射，显微硬度测定等手段研究了ＺｎＡｌ４０合金的时效分解我并通过ＳＥＭ和ＴＥＭ观察了时效过程中合金的微观组织变化。结果表明，在时效过程中，合金的硬度发生变化，硬度峰值与时效值温度有关，且着时效时间延长，α－Ａｌ的点阵参数增加。在时效过程中，过饱和固溶体α－Ａｌ的点阵参数增加。在时效过程中，过饱和固溶体α‘Ａｌ发生分解，在晶界处通过非连续没淀反应，形成粒状组织；晶内通过ｓｐｉｎｏｄａｌ分解     

Cu 5Ni 4Sn 3Al合金的时效强化

根据合金的力学和电学性能, 利用ＸＲＤ,ＴＥＭ 和ＳＥＭ 技术研究了Ｃｕ５Ｎｉ４Ｓｎ３Ａｌ 合金的时效强化。结果表明：３５０ ℃下时效时, 力学性能增加; 边带分析有边带效应, 且随时效时间的增加调幅波长增加。电镜下观察到调幅结构, 说明该合金是调幅分解强化的合金。同时, 铝的加入没有改变合金的相结构, 但是, 对合金的强化起着重要作用。实验结果还表明, 合金在时效过程中, 调幅分解的同时还形成ＤＯ２２（ＴｉＡｌ３） 型结构的Ｎｉ３Ｓｎ 化合物相     

双重时效的低温形变热处理对Al-Mg-Si-RE合金力学性能的影响

研究了双重时效的低温形变热处理（ＬＴＨＴ）对ＡｌＭｇＳｉＲＥ合金力学性能的影响。双重时效的低温形变热处理使ＡｌＭｇＳｉＲＥ合金获得抗拉强度σｂ＝３５０ＭＰａ,σ０．２＝２９１ＭＰａ和延伸率δ＝６％的最佳综合力学性能。显然用这种处理工艺比用固溶淬火＋时效的普通热处理工艺优越。研究表明,双重时效的低温形变热处理是有效提高ＲＥＡｌ合金强度的一种值得推广的工艺。     

喷射沉积Al-3．8Li-0．8Mg-0．4Cu-0．13Zr合金的显微组织与拉伸性能

采用新型的喷射沉积快速凝固工艺制备了Ａｌ３．８Ｌｉ０．８Ｍｇ０．４Ｃｕ０．１３Ｚｒ合金，并对合金的显微组织与拉伸性能进行了实验研究。实验结果表明，沉积态合金组织为细小、均匀的等轴晶，晶粒尺寸大多在５～２０μｍ范围内。经热挤压后合金组织中的晶粒呈“砖块”状或“竹节”状形貌特征，晶界上破碎的氧化物很少。时效析出不规则形状的δ′相粒子和球壳状β′δ′复合沉淀相。δ′粒子的粗化速度较快，δ′粒子间距随时间增大的趋势不明显。喷射沉积ＡｌＬｉ合金短时间时效（１９０℃，１０ｈ）即可达到峰时效状态，此时材料的综合性能最优（σｂ＝５３４ＭＰａ，σ０．２＝４８０ＭＰａ，延伸率为１０％）。与粉末冶金ＡｌＬｉ合金相比，材料的塑性明显改善而强度相当。     

快速凝固Al－Cu－Mg合金的时效特征

对离心雾化法制得的快速凝固Ａｌ－Ｃｕ－Ｍｇ合金的时效特征进行了研究。结果表明,随时效温度的升高,快速凝固Ａｌ－Ｃｕ－Ｍｇ合金的时效硬度峰值增加,且达峰值后硬度下降缓慢。在连续加热时效过程中,快速凝固Ａｌ－Ｃｕ－Ｍｇ合金有Ｓ”相形成过程,且Ｓ’相形成长大过程比较缓慢。从时效析出激活能、连续加热过程分析等方面进行了解释和验证。     

快速凝固Al—Cu—Mg合金的时效特征

对离心雾经法制得的快速凝固Ａｌ－Ｃｕ－Ｍｇ合金的时效特征进行了研究。结果表明，随时效温度的升高，快速凝固Ａｌ－Ｃｕ－Ｍｇ合金的时效硬度峰值增加，且达峰值后硬度下降缓慢。在连续加热时效过程中，快速凝固Ａｌ－Ｃｕ－Ｍｇ合金有Ｓ相形成过程，且Ｓ相形成长大过程比较缓慢。     

Al－Mg－Li－Ag－Zr合金的时效特性

研究了添加不同量的Ｌｉ对Ａｌ－Ｍｇ－Ａｇ－Ｚｒ合金时效组织和机械性能的影响。通过时效硬度、拉伸强度和延伸率的测试，以及ｘ射线衍射分析和ＴＥＭ观察，证明在Ａｌ－Ｍｇ－Ａｇ－Ｚｒ合金中加入Ｌｉ可使合金得到显著的时效硬化和强化，但仅当Ｌｉ的含量在１．７５％时，该合金才具有优良的综合力学性能；在含Ｌｉ量较低的Ａｌ－Ｍｇ－Ｌｉ－Ａｇ－Ｚｒ合金中可生成Ｔ相，且Ｔ相的生成有利于该合金综合性能的提高。     

Al—Mg—Li—Ag—Zr合金的时效特性

研究了添加不同量的Ｌｉ对Ａｌ－Ｍｇ－Ａｇ－Ｚｒ合金时效组织和机械性能的影响。通过时效硬度、拉伸强度和延伸率的测试，以及Ｘ射线衍射分析和ＴＥＭ观察，证明在Ａｌ－Ｍｇ－Ａｇ－Ｚｒ合金中加入Ｌｉ可使合金得到显著的时效硬化和强化，但仅当Ｌｉ的在１．７５％时，该合金才具有优良的综合力不性能；在含Ｌｉ量较低的Ａｌ－Ｍｇ－Ｌｉ－Ａｇ－Ｚｒ合金中生成Ｔ相，且Ｔ相的生成有利于该合金综合性能的提高。     

Ni-Ti合金时效早期相变规律的研究

通过ＴＥＭ分析对Ｎｉ１０％Ｔｉ（％，质量分数，下同）合金时效早期相变过程的研究表明Ｎｉ１０％Ｔｉ合金过饱和固溶体先通过调幅分解机理分解为贫、富溶质区；随后富溶质区发生有序化，最后形成Ｌ１２型有序相Ｎｉ３Ｔｉ。同时发现，淬冷抑制了该合金固溶体的相分解过程。ＮｉＴｉ合金时效相变过程中存在调幅分解与有序化两种失稳模式共存现象。     

Cu—5Ni—4Sn—3Al合金的时效强化

根据合金的力学和电学性能,利用ＸＲＤ,ＴＥ几ＳＥＭ技术研究了Ｃｕ－５Ｎｉ－４Ｓｎ－３Ａｌ合金的时效强化。结果表明：３５０℃下时效时,力学性能增加,边带分析有边带效应,且随时效时间的增加调幅波长增加。电镜下观察到调幅结构,说明该合金是调幅分解强化的合金。同时,铝的加入没有改变合金的相结构,但是,对合金的强化起着重要作用,实验结果还表明,合金在时效过程中,调幅分解的同时还形成ＤＯ２２（ＴｉＡｌ３）型结     

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.