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951.
泡沫金属力学性能的若干问题 总被引:8,自引:0,他引:8
刘培生 《稀有金属材料与工程》2004,33(5):473-477
泡沫金属在结构方面的应用口益增多,其力学性能随之显得越来越重要。本文列举了该材料的一些结构用途,在强化其力学性能研究意识的同时,提出了泡沫金属双向拉伸性能研究的基础性和必要性。并从其应用发展趋势、制备方法和结构特点出发,指出该材料双向力学性能与孔率关系研究的重要意义。 相似文献
952.
化学镀Ni-P镀层的组织形貌与耐蚀性 总被引:4,自引:0,他引:4
通过观察化学镀Ni-P镀层沉积过程形貌及形貌变化特征,研究了用不同镇液化学镀所获得的不同含磷量镀层的形貌变化,并指明在含磷量为(4.0~7.0)%范围内,镀层成胞状和菜花状的腐蚀破坏常常首先沿胞壁进行,且大胞中心易出现腐蚀裂纹和沟槽。若胞的大小均匀,凸凹不明显,胞表面光滑,含磷量均匀,则耐蚀性好。 相似文献
953.
A WC-Co coating was sprayed by the high-velocity oxyfuel process using a feedstock of tungsten carbide clad with cobalt. The
structure of the sprayed coating was characterized by x-ray diffraction (XRD), differential scanning calorimetry (DSC), and
differential thermal analysis (DTA). It was found that an amorphous phase of Co-W-C ternary alloy observed as a large, broad
peak in the XRD pattern can be formed in the as-sprayed WC-Co coating. The DSC, DTA, and XRD analyses revealed that the amorphous
phase crystallized at a temperature of around 873 K to metallic cobalt, Co6W6C, and tungsten with appreciable precipitation of free carbon. The heat treatment of as-sprayed WC-Co coating at a high temperature
of 1173 K suggests that annealing at a temperature higher than about 1104 K will promote the reaction of tungsten and cobalt
with carbon to form the complex carbide C06W6C. 相似文献
954.
X.H.You F.Wang L.C.Wang 《金属学报(英文版)》2004,17(3):279-282
A new technique, powder compact foaming process for the production of aluminum foams has been studied in this article. According to this method, the aluminum powder is mixed with a powder foaming agent (Till2). Subsequent to mixing, the powder blend is hot compacted to obtain a dense semi-finished product. Upon heating to temperatures within the range of the melting point, the foaming agent decomposes to evolve gas and the semi-finished product expands into a porous cellular aluminum. Foaming process is the key in this method. Based on experiments, the foaming characteristics were mainly analyzed and discussed. Experiments show that the aluminum-foam with closed pores and a uniform cell structure of high porosity can be obtained using this method by adjusting the foaming parameters: the content of foaming agent and foaming temperature. 相似文献
955.
X.X.Guo J.S.Liu 《金属学报(英文版)》2004,17(3):323-326
The adaptive remeshing technique for quadrilateral elements consists of modules the trigger of remeshing, the new mesh generation, adaptive refinement and interpolation of field variables. The new adaptive mesh generation is the key problem. First, a coarse mesh is created by using “loop algorithm“. Subsequent local mesh adaptive refinement is performed based on effective strain. Finally, a typical example of upsetting is given to test efficient of techniques, from which it is verified that the remeshing algorithm developed here exhibits good performance and has high accuracy. 相似文献
956.
脱除重油中有害金属杂质新技术 总被引:2,自引:0,他引:2
用化学药剂在一定条件下进行反应后用水萃取,并用
电脱水的方法脱除金属.研究了注药剂量、反应温度和反应时间等因素对脱除率的影响. 相似文献
957.
958.
Due to complexities of draw-bead restraining force calculated according to theory and depending on sheet metal forming properties experiment testing system, a simplified method to calculate draw-bead restraining force is put forward by experimental method in cup-shaped drawing process. The experimental results were compared with numerical results and proved agreement. It shows the method is effective. 相似文献
959.
HUANG Jianshun CHEN Junming Shanghai Institute of Metallurgy Academia Sinica Shanghai China Research Associate Shanghai Institute of Metallurgy Academia Sinica Shanghai China 《金属学报(英文版)》1993,6(7):69-75
Crystal structure of γ-Li_xFe_2O_3,inserted Li electrochemically,was studied by Moss-bauer spectroscopy together with X-ray diffraction,XPS and electrochemical method,Onthe insertion of Li at low current density,the crystal structure is keeping original spinel;while at higher current density or by thermal activation,owing to violent movement ofLi~+ ions,part of crystal structure transforms into rock type similar to face-centeredcubic structure of ferrous oxide.The transition channels during insertion of Li~+ ions andlimitation of Li~+ ions inserted were discussed. 相似文献
960.
L. H. Lang D. C. Kang S. H. Zhang Z. R. Wang S. J. Yuan K. B. Nielsen J. Dancket ) Department of Materials Engineering Harbin Institute of Technology Harbin China ) Aalberg University Denmark 《金属学报(英文版)》2000,13(2):476-480
1.~nonHydridapawhcdeepdrawing(HDD)belongstothefieldofsheetmetalfoeingandcanbeaPPliedinthefieldofautomotive,aerospace,drilitaryindustryetc.Ithasbeenrecognizedwidelyintheworld["'j.Fig.Ishowsitsprinciple:TheliqUidthatisfilledinthe~ngdiecavitywillbepressedwhenthepunchgoesdownsothattheeffectoffrictionkeepingandoverflowlubricatingcanbeformed,astherestilt,thefoeinglicitofsheetmetalwillbeimprovedareailvandthegualitVofthefinishedpartswillbeup~ed.BecauseofmanyadvantagesofHDDprocees,ithasbeenwidelys… 相似文献