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High Temperature Gaseous Rare-Earth Permeation of Polyoxotungstates:An New Effective Method for the Preparation of Tungsten Bronzes 郭元茹1,韦永德1,李中华1,周百斌1 (1.Department of Applied Chemistry, Harbin Institute of Technology, Harbin 150001, China) Abstract:New polyoxometalate α-K12H3[Y(BW11O39)2]·25H2O was synthesized and treated by high temperature gaseous rare earth permeation to prepare tungsten......
PREPARATION OF NANOSTRUCTURED TUNGSTEN POWDERS曹立宏,傅磊,樊友三摘 要:<正>The preparation of nanostructured tungstenpowders has been studied by using.... Tungsten powders ofmean particle size of 40 nanometer,and specific surface areaof 3×104m2/kg have been prepared. The shape of nanostruc-tuted tungsten powders is sphere.关键词:......
Microstructure and properties of ultra-fine tungsten heavy alloys prepared by mechanical alloying and electric current activated sintering LI Xiao-qiang(李小强), XIN Hong-wei(辛红伟), HU Ke(胡 可), LI...: The microstructure and properties of the 93W-4Ni-2Co-1Fe (mass fraction, %) tungsten heavy alloys prepared by mechanical alloying and electric current activated sintering from mixed elemental powders were......
Comparative study on discharge conditions in micro-hole electrical discharge machining of tungsten carbide (WC-Co) material Hyun-Seok TAK1, Chang-Seung HA2, Dong-Hyun KIM2, Ho-Jun LEE2.... For machining difficult-to-cut materials, such as tungsten carbide, micro-electrical discharge machining(EDM) is one of the most effective methods for making holes because the hardness is not a dominant......
Structural Analysis and Electrical Property of Tungsten Bronze Prepared by Rare Earth Gaseous Permeation 韦永德1,陈刚1,李中华1,苏铭汉1,李昕1 (1.Department of Applied Chemistry, Harbin Institute of Technology, Harbin 150001, China) Abstract:The cubic sodium tungsten bronzes, NaxWO3(x=0.854 and 0.814)were prepared by rare earths gaseous permeation method. Structural analysis was carried out by Rietveld......
-earth- oxygen interactions, which inhibits grain growth by reducing the surface diffusivity of tungsten skeleton [30,31]. Currently, there are three routes to dope the rare-earth oxide particles into refractory metals: (I) Solid-solid (SS). Lu2O3 particles could be doped into the tungsten matrix by ball milling to prepare the W-Lu2O3 alloy [32]; (II) Liquid-solid (LS). YAR et al [33,34] produced......
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Partial melting and re-solidification in partially melted zone during gas tungsten arc welding of AZ91 cast alloy T. P. ZHU1, Z. W. CHEN2, W. GAO1 1. Department of Chemical... in constitutional liquation in the original interdendritic regions and in the formation of a partially melted zone (PMZ). In this study, gas tungsten arc welding (GTAW) and partial melting (simulated using......
A NEURAL NETWORK FOR WELD PENETRATION CONTROL IN GAS TUNGSTEN ARC WELDING J.Q. Gao1,C.S. Wu1,Y.H. Zhao1 (1.Institute of Materials Joining, Shandong University, Jinan 250061, China) Abstract:Realizing of weld penetration control in gas tungsten arc welding requires establishment of a model describing the relationship between the front-side geometrical parameters of weld pool and the back-side......
temperature ablation resistance and thermophysical properties of tungsten matrix composites reinforced with ZrC particles[J]. Journal of Materials Science, 2001, 36(19): 4625-4631. [7] MARIANO E, GERARDO H...,喉部以机械剥蚀为主,以熔化烧蚀及热化学烧蚀为辅,其烧蚀程度最为严重;收敛段为机械剥蚀和热化学烧蚀,其烧蚀程度次之;而扩散段则发生热化学烧蚀,其烧蚀程度最低. 关键词:等离子喷涂成形;钨喉衬;热等静压;烧蚀 中图分类号:TG146 文献标志码:A Ablation property of tungsten nozzle......