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排序方式: 共有6359条查询结果,搜索用时 15 毫秒
131.
The experiments for rheologic behaviors of semisolid continuous casting billets of A356 alloy in semisolid state had been carried out with a multifunctional rheometer. The results show that the deformation rate increases with loading time, the maximum strain reaches to 120% (which is one time larger than that of traditional mold casting billet) and the strain can be rapidly eliminated to 10% after unloading. Moreover, there is a critic stress for billet deformation even in semisolid state, which is named as critic shear stress. This stress increases with the decreasing of heating time. The theologic behaviors can be expressed by five elements mechanical model (H_2- [N_1|H_2]-[N_2|S]) and can be modified with the increasing of heating time. 相似文献
132.
WEN Jiu-ba ZHANG Wei LI Xiao-yuan LI Quan-an School of Materials Science Engineering Henan University of Science Technology Luoyang China . School of Materials Science Engineering Xi''''an University of Technology Xi''''an China 《材料热处理学报》2004,25(5)
THE HOT-DIPPED ALUMINUM technology of metalsurface is a traditional technology of surfacedisposal[1|21adding some rare-earth during thehot-dipped aluminum process can effect the technologyof hot-dipped aluminum and the microstructure ofhot-dipped aluminizing layer'31,so the surfacecapability of metal is greatly increased,forming a newtechnology of hot-dipped aluminum.After hot-dippedaluminum steel,metal surface has excellent corrosionresistance,high temperature oxidation,especiallycorro… 相似文献
133.
ZHAO Xuehui ) HUANG Kelong) JIAO Feipeng) LI Zhiaojian) and PENG Xiahui) ) College of Chemistry Chemical Engineering Central South University Changsha China ) Chemistry Department Hunan Technology BOE Science University Zhuzhou China 《稀有金属(英文版)》2006,(2)
1. Introduction Rare earth elements have an important function inlife process. The fluorescence enhancement of lan-thanides in aqueous solutions has therefore becomean area of active study in trace-level estimation oflanthanides using spectrofluorimetry [1]. Its possiblemechanism and application as fluorescence probesin biological systems have also attracted attention inrecent years [2]. Generally, fluorescence enhance-ment can be achieved through ligand sensitization.Various ligands have bee… 相似文献
134.
FAN Jin-juan WANG Quan-sheng ZHANG Wei-fang . Failure Analysis Center of Beijing Institute of Aeronautical Materials Beijing China .Department of material science engineering Beijing Institute of Technology Beijing China 《材料热处理学报》2004,(5)
THERMAL BARRIER COATINGS can holdbackintrusion of high temperature,high heat to increaseapplied temperature and life of substrate metal parts,and have been applied on heat position of rocket,satellite,aero engine and gas engine"31.But thermalstresses are produced during thermal shock due tomismatch of thermal properties between ceramiccoatings and substrate metal,therefore thermal shockproperties of coatings are very poor.Gradient thermalbarrier coatings make materials gradually chang… 相似文献
135.
GAO Bo HAO Sheng-zhi ZOU Jian-xin JIANG Li-min ZHOU Ji-yang'''' DONG Chuang .State Key Lab. of Materials surface Modification by Laser Ion Electron Beams Dalian China .Department of Materials Engineering Dalian University of Technology Dalian China 《材料热处理学报》2004,25(5)
MAGNESIUM ALLOYS exhibit high strength toweight ratio and stiffness and are finding theirapplications in air,automobile and electronic industries.Despite the worldwide growing interests inmagnesium alloys,their inferior wear resistance is aserious impediment.Considering that wear is asurface-related behavior,surface modification canresolve the problem.Recently,intense and pulsed energetic beams areemerging as new and effective methods for surfacemodification.The High Current Pulsed Ele… 相似文献
136.
XU Xiang-yang HAN Jian-min ZHONG Min-lin LIU Wen-jin . Institute of Materials Science Engineering Beijing Jiaotong University Beijing China . Department of Mechanical Engineering Tsinghua University Beijing China 《材料热处理学报》2004,25(5)
NiAl intermetallic alloys are potential high temperaturestructural materials in aeronautical and astronauticalindustries[1].However,the poor ductility andtoughness at room temperature severely restrict theirengineering applications[2,3].It is important todevelop new technology to product intermetallicmaterials for the improvement of the comprehensiveproperties and the workability.Laser powder depositionhas been used to synthesize many new materials.Furthermore,if incorporated with rapid proto… 相似文献
137.
Chemical composition of open-hearth furnace slag isimportant for the metal and casting quality. The chemicalcomponents of slag need to be analyzed precisely andaccurately.For a long time the composition determination of slag ismade chemically, which involves complicated processes,long analytical cycle, high cost and tedious work. A greatmany successful applications of ores analysis by x-rayfluorescence spectrometry (XRF) have been reported[1-4].Powder-fused wafer is a sampling method used in… 相似文献
138.
Shen Yifu Feng Zhongchao Chen Jizhi Liang Yong Institute of Metal Research The Chinese Academy of Sciences Shenyang Department of Materials Science Engineering Nanjing University of Aeronautics an 《中国有色金属学会会刊》1997,(4)
SURFACEMODIFICATIONONSTEELBYRAREEARTHANDLASERTREATMENT①ShenYifu1,2,FengZhongchao1,ChenJizhi1,LiangYong11InstituteofMetalResea... 相似文献
139.
LIU Yan HUI Xidong and WANG Huanrong) Department of Materials Science Engineering Shandong Institute of Architecture Engineering Jinan China) State Key Laboratory for Advanced Metals Materials University of Science Technology Beijing Beijing China) Key Laboratory of Liquid Structure Heredity of Materials Ministry of Education Shandong University Jinan China 《稀有金属(英文版)》2003,22(4)
The influence of pre-annealing on thermal stability of the amorphous Zr70Cu20Ni10 alloy was reported by em-ploying the differential scanning calorimetry (DSC) and high-resolution transmission electron microscopy (HRTEM) tech-niques. It has been observed that the supercooled liquid region decreases with increasing the annealing time under isothe-mal conditions, indicating that the thermal stability of the amorphous Zr70Cu20Ni10 alloy decreases gradually. HRTEM ob-servations reveal that there exist some ordered atomic clusters in the amorphous matrix at the relaxation stage. These or-dered atomic clusters can be regarded as precursors for the precipitation of the crystalline phases in the subsequent crystal-lization process. The reasons resulting in the decrease in thermal stability of the amorphous Zr70Cu20Ni10 alloy with anneal-ing time are discussed through the Gaussian decomposition for the radial distribution function of the amorphous Zr70Cu20Ni10 alloy. 相似文献
140.
Lü Cheng ZH ANG Li-wen .State Key Laboratory for Materials Modification by Later Ion Electron Beams Dalian University of Technology Dalian China .School of Materials Science Engineering Dalian University of Technology Dalian China 《中国有色金属学会会刊》2006,16(6):1386-1390
1Introduction The TC4alloy mounting part is an important part of aeronautic engine.Currently,these mounting parts are mainly manufactured by metal cutting,which is expensive and requires a lot of manufacturing time.Furthermore,in this way the forging flow… 相似文献