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structure, aluminum foam has great potential application in fields such as sound insulation and noise reduction. In this paper, the author researches on the sound insulation property of Al-Si closed-cell... in such fields as sound insulation and noise reduction. 2 Experimental 2.1 Preparation of aluminum foam materials Al-Si closed-cell aluminum foams were produced by molten body transitional foaming......
but the lowest friction coefficient also shows an increase. However, the wear rate and braking noise of the friction material monotonously decrease with increasing zinc content. This effect may be attributed... on the friction surface. The wear resistance of brake friction materials was improved due to abrasive particles, resulting in the increase of minimum friction coefficient (see Fig. 5). 4.2 Braking noise......
; (7b) where D is a coefficient which dominates the amount of the drag reduction and is the function...J. Cent. South Univ. Technol. (2008) 15(s1): 243-246 DOI: 10.1007/s11771-008-355-6 Drag reduction by linear viscosity model in turbulent channel flow of polymer solution WU Gui-fen......
A strength reduction method based on double reduction parameters and its applicationYUAN Wei(袁维), BAI Bing(白冰), LI Xiao-chun(李小春), WANG Hai-bin(汪海滨) (State Key Laboratory of Geomechanics and Geotechnical Engineering (Institute of Rock and Soil Mechanics, Chinese Academy of Sciences), Wuhan 430071, China)Abstract:In the traditional strength reduction method, the cohesion and the friction angle......
:A 文章编号:1672-7207(2019)05-1263-08 Band gap properties and noise reduction performances of periodic noise barriers in rail transit YI Qiang1, 2, WANG Yuhang1... erect sound barrier of the same mass, the noise reduction of periodic sound barrier increases by 2-3 dB, while noise reduction of the fully enclosed sound barrier increases by 3-5 dB after the band gap......
of reduction strength input to the model, and Fs(t) is the safety factor or reduction coefficient at corresponding time. Carrying on the iteration to pilot calculation continuously, the safety factor under.... In the computation analysis process, firstly, the parameters c=30 kPa and φ=20? are carried on to reduce at initial time, then, the reduction coefficient Fs(t) is increased unceasingly by taking 0.1......
J. Cent. South Univ. (2017) 24: 1-8 DOI: 10.1007/s11771-017-3402-3 Galvanic corrosion behavior of plain carbon steel-B4C composite in 3.5% NaCl solution with electrochemical noise S. H. Ettefagh... microscopy; potentiodynamic polarization; electrochemical noise 1 Introduction Adding hard ceramic particles to a metal matrix (MMC) increases resistance to abrasion and hardness and can generate......
Effect of Rare Earths on Diffusion Coefficient and Transfer Coefficient of Carbon during Carburizing 刘志儒1,阎牧夫1 (1.School of Materials Science and Engineering, Harbin Institute of Technology,) Abstract:The diffusion coefficient of carbon in surface layer of steel-20 rare earth carburized at 880 ℃ and 900 ℃ for 8 h was calculated by substituting the measured layer depths into the diffusion......
of high energy load, the friction coefficient increases, the abrasion loss decreases and the occurrence of friction noise reduces with the increase of Cu-Sn alloy powder content. When the copper-tin...比较完整,继续增加含量时,由于其有一定的润滑效果,又会略微降低材料摩擦因数. 图5 不同制动初速度时样品的摩擦因数与压力的关系 Fig. 5 Relationship between friction coefficient and pressure of samples at original braking speeds 衰退试验摩擦因数随样品铜锡合金粉含量的变化如图......