Hong M.-Q.,Zhuzhou Professional Technology College |
Yin S.-X.,Zhuzhou Lince Group Casting Co.
Zhuzao/Foundry | Year: 2011
Inlay casting iron core sometimes looses in axial direction from the running cast aluminum impeller, then the fan will cause fault such as vibration and abnormal voice etc. The effects of the two different configurations of the cast aluminum iron core on the quality of the impeller were analyzed in this paper. Structural design of inlay core and casting technology of impeller were briefly explained.
Chen S.-H.,University of South China |
Chen M.-M.,Zhuzhou Professional Technology College |
Xu D.-C.,Southern Medical University |
He H.,University of South China |
And 3 more authors.
Surgical and Radiologic Anatomy | Year: 2011
Purpose: To find out the advantages and insufficiency of the 3D reconstruction and traditional anatomy by comparing them with each other. Methods: 1. Infused with the radio-opaque material from the arteries and veins, respectively, fresh lower extremity specimens were subjected to spiral CT scanning and then 3D reconstruction was conducted to obtain 3D vessels. 2. Anatomizing the specimens to show the vessel system. 3. Comparing the images of 3D reconstruction and photos of the dissected specimens. Results: 3D software could dissect and reconstruct the bones, vessels, skin and muscles, and the reconstructed photos could be shown, respectively or combinedly. On the other hand, the course, distribution, and anastomoses of the vessels could be viewed from different aspects and different layers, but the results were not completely correct, so they were not suitable for data acquisition. While the vessel systems could be observed clearly on the dissected specimens, so could the origin, course, distribution and the anastomoses of any vessel. The data acquisition could be conducted. Conclusions: The method of angiography with 3D reconstruction is very good and has considerable advantages for observing the 3D state of human blood vessels, and their distribution at different angles and different levels, but it cannot totally represent or replace the traditional dissected specimens. © 2010 Springer-Verlag.
Li J.,Hunan Normal University |
Li J.,Zhuzhou Professional Technology College |
Wang L.,Hunan Normal University
Mathematical Problems in Engineering | Year: 2010
Criteria are established for existence of three solutions to the boundary value problems Lx = f(t, x), w1x(0) - w2x′(0) = 0 = w3x(1)+w4x′ (1), where L x: = - (px′) ′ + q x. Here, p∈C1 [ 0,1 ], p>0, q∈C [ 0,1 ], q≥0. © 2010 L.Wang and J. Li.
Xia Z.,Zhuzhou Professional Technology College |
Li Z.,Hunan University of Technology
Advanced Science Letters | Year: 2013
With the orthogonal experiment approach, the boronizing process parameters such as the boronizing temperature, the amount of boron carbide, potassium fluoborate, silicon carbide and rare earth used were determined, and the thickness of the boriding layer is less than 0.25 mm. By co-permeation of boron, chromium, rare earth and carbon, the hardness of the transition layer is improved and the service life of the mold used for fabricating the sand-lime brick is achieved at 1.2 million times. Through testing with appropriate fast quenching oil, the hardness of the substrate after boronizing process is guaranteed to meet the technological requirements and its deformation is also ensured to meet the application requirements. © 2013 American Scientific Publishers All rights reserved.
Liu J.,Zhejiang University |
Huo X.,Zhuzhou Professional Technology College
Advanced Materials Research | Year: 2011
In this paper, we consider the Poisson problem with homogeneous Dirichlet boundary conditions on the bounded open domain Ω ∈ R3 and analyze convergence phenomena that appear by using cubic serendipity block elements with thirty-two degrees of freedom. By means of the standard Legendre polynomial technique, we derive an error estimate, which is not superconvergent and shows this serendipity element has not pointwise supercloseness properties. © (2011) Trans Tech Publications, Switzerland.
Luo H.,Zhuzhou Professional Technology College
Tezhong Zhuzao Ji Youse Hejin/Special Casting and Nonferrous Alloys | Year: 2013
The effects of different rolling rouths including cross rolling (CR), differential speed rolling (DSR) and differential speed cross rolling (DSCR) on microstructure, mechanical properties and corrosion resistance of AZ31 magnesium alloy sheets were investigated. The results show that the mechanical properties and corrosion resistance of the alloy can be improved significantly as a result of controlling microstructure and basic texture by changing rolling rouths. Significant grain refinement and lower texture intensity can be obtained during DSCR as a result of the direction change of shear deformation, which consequently results in the higher mechanical properties and corrosion resistance than those of CRed and DSRed sheets.
Hong M.-Q.,Zhuzhou Professional Technology College
Zhuzao/Foundry | Year: 2012
Aluminum alloy was melted by the medium-frequency coreless induction furnace. During the late stage of melting, the larger hump phenomenon that can increase the inspiratory tendency of the melt appeared in the aluminum melt by the eddy current stirring, which resulted in the high gas content of the melt. A large number of pinholes exist in the casting because of the high gas content that is not easy to excluded after refining. This article aims to make deep analysis on aluminum alloy melting process in medium-frequency coreless induction furnace, and describes the main causes of pinhole formation, namely eddy current stirring aluminum liquid during melting process. In the meantime, paper introduces ways that prevent the hump phenomenon from appearing and reduce increasing tendency of aluminum-liquid inspiratory by proper building of furnace and adjusting of the crucible height.
Yang G.,Zhuzhou Professional Technology College
Applied Mechanics and Materials | Year: 2011
This article briefly introduces the structure of the tooth shape silence chain. The touch point of the roll pins separate when the chain goes around the sprocket gear. It deduces the dimensions of the offset angle α and the roll pin angle θ with mathematics method. This preface shows when the outer circular arc R≈0.5P, the fluctuation of the chain transmission speed is the least. When R=0.5P, We deduce the size of the roll pin by the value of α, θ, R and the ultimate tensile strength, then we can get the structure parameter of the chain plate hole by the method of geometrical construction. © 2011 Trans Tech Publications.
Xia Z.-B.,Zhuzhou Professional Technology College
Jinshu Rechuli/Heat Treatment of Metals | Year: 2011
Effect of temperature, carbon potential, ammonia flow and holding time on the case hardness, effective hardened depth and surface microstructure of the shifting fork was studied by adopting orthogonal experiment. The optimized parameters of 20CrNiMo steel shifting fork are following, 840 °C holding for 30 min, carbon potential is 1. 0%, ammonia flow is 10 L/min.
Sun G.,Zhuzhou Professional Technology College
Fenmo Yejin Jishu/Powder Metallurgy Technology | Year: 2013
Powder metallurgy parts are used in automobile industry more and more widely. Only automatic forming presses are used, it' s possible to realize mass production, costs reduction, efficiency improvement. But automatic forming press set is commonly high, and mould length size is larger. The production problem can be solved effectively by mould design of PM worm wheel shaft sleeve in automobile engine due to mould manufacturing difficulty.