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Influence of Friction Condition on Cold Upsetting of Tube Flange

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Journal of Materials Science & technology 2001年第1期17卷 155-156页

作者： Jun LU Zhongjin WANG and Mingxue ZHANG school of Materials Science and Engineering, har.in institute of technology, har.in 150001, china har.in Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China

FEM is used to analyze the influence of interface friction on the material flow and the cause of forming defect in the cold upsetting of tube flange. Based on the FEM simulation results, the relationships between flange width and the extreme friction factors are established. The concept of forming limit diagram for cold upsetting of tube flange is presented.

关键词： Influence of Friction Condition on Cold Upsetting of Tube Flange

Investigation of modification design of the fan stage in axial compressor

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Journal of Thermal Science 2010年第2期19卷 105-109页

作者： Xun ZHOU,Peigang YAN and Wanjin HAN Energy Science and Engineering school,har.in institute of technology,har.in,150001,china Energy Science and Engineering school Harbin Institute of Technology Harbin China

The S2 flow path design method of the transonic compressor is used to design the one stage fan in order to replace the original designed blade cascade which has two-stage transonic fan *** the modification design,the camber line is parameterized by a quartic polynomial curve and the thickness distribution of the blade profile is controlled by the double-thrice ***,the inlet flow has been pre-compressed and the location and intensity of the shock wave at supersonic area have been controlled in order to let the new blade profiles have better aerodynamic *** computational results show that the new single stage fan rotor increases the efficiency by two percent at the design condition and the total pressure ratio is slightly higher than that of the original *** the same time,it also meets the mass flow rate and the geometrical size requirements for the modification design.

关键词： Modification design Fan Compressor Numerical simulation

Modeling of Heat Transfer and Solidification Process of Spray Formed Billet

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Journal of Materials Science & technology 2001年第1期17卷 101-102页

作者： Fuyang CAO Chengsong CUI and QingChun LI school of Materials Science and Engineering, har.in institute of technology, har.in 150001, china har.in Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China

In this paper, modeling of heat transfer and solidification process of spray formed billet was established. Thermal profiles of billet at various spray time and under various spray forming conditions were calculated n... 详细信息

关键词： Solidification Process solidification process simulation results spray forming heat transfer

Solution to the problem of ant being stuck by ant colony routing algorithm

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The Journal of china Universities of Posts and Telecommunications 2009年第1期16卷 100-105,110页

作者： ZHAO Jing , TONG Wei-ming school of Electrical Engineering and Automation, har.in institute of technology, har.in 150001, china [a]school of Electrical Engineering and Automation har.in institute of technology har.in 150001 china

Many ant colony routing （ACR） algorithms have been presented in recent years, but few have studied the problem that ants will get stuck with probability in any terminal host when they are searching paths to route packets around a network. The problem has to be faced when designing and implementing the ACR algorithm. This article analyzes in detail the differences between the ACR and the ant colony optimization （ACO）. Besides, particular restrictions on the ACR are pointed out and the three causes of ant being-stuck problem are obtained. Furthermore, this article proposes a new ant searching mechanism through dual path-checking and online routing loop removing by every intermediate node an ant visited and the destination host respectively, to solve the problem of ant being stuck and routing loop simultaneously. The result of numerical simulation is abstracted from one real network. Compared with existing two typical ACR algorithms, it shows that the proposed algorithm can settle the problem of ant being stuck and achieve more effective searching outcome for optimization path.

关键词： ACR algorithm ACO route searching mechanism network routing network topology structure

Superplasticity and Superplastic Bulging Behavior of ZrO_2/Ni Nanocomposite

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Journal of Wuhan University of technology(Materials Science) 2011年第1期26卷 56-60页

作者：丁水 aerospace Research institute of Materials and Processing technology

ZrO2/Ni nanocomposite was produced by pulse electrodeposition and its superplastic properties were investigated by the tensile and bulging tests. The as-deposited nickel matrix has a narrow grain size distribution with a mean grain size of 45 nm. A maximum elongation of 605% was observed at 723 K and a strain rate of 1.67×10-3s-1 by tensile test. Superplastic bulging tests were subsequently performed using dies with diameters of 1 mm and 5 mm respectively based on the optimal superplastic forming temperature. The effects of forming temperature and gas pressure on bulging process were experimentally investigated. The results indicated that ZrO2/Ni nanocomposite samples can be readily bulged at 723 K with H/d value （defined as dome apex height over the die diameter） larger than 0.5, indicating that the nanocomposite has good bulging ability. SEM and TEM were used to examine the microstructure of the as-deposited and bulged samples. The observations showed that significant grain coarsening occurs during superplastic bulging, and the microstructure is found to depend on the forming temperature.

关键词： superplasticity bulging microstructure ZrO2/Ni nanocomposite

Oxidation-induced strengthening behavior of reaction formed Al_4SiC_4 ceramics

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Rare Metals 2007年第S1期26卷 94-98页

作者： HUANG Xiaoxiao1,2),WEN Guangwu1,3),LIU Ruitang2),and ZHENG Xin1)1) school of Materials Science and technology,har.in institute of technology,har.in 150001,china 2) school of Material Science and Chemical Engineering,har.in Engineering University,har.in 150001,china 3) school of Materials Science and technology,har.in institute of technology at Weihai,Weihai 264209,china har.in Inst Technol Sch Mat Sci & Technol Harbin 150001 Peoples R China har.in Inst Technol Sch Mat Sci & Chem Engn Harbin 150001 Peoples R China har.in Inst Technol Sch Mat Sci & Technol Weihai 264209 Peoples R China

The bending strengths of Al4SiC4 ceramics were investigated from room temperature to 1300 ℃ in air and in vacuum,*** is a novel property that the bending strength increases with increasing test temperatures up to 1300 ℃ in *** strength value of Al4SiC4 ceramics is 449.7 MPa at 1300 ℃ in air,which is about 1.5 times of that at room temperature(300 MPa).The self-healing behavior of the flaws on the specimen surface due to the oxidation of the surface layer of the Al4SiC4 ceramics is considered as the main enhancement mechanism at high temperatures.

关键词： calcination and hot pressing surface strength Al_4SiC_4

Numerical Simulation of Transport Phenomena in Solidification of Multicomponent Ingot Using a Continuum Model

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Journal of Materials Science & technology 2001年第1期17卷 67-68页

作者： Daming XU Guangju SI Geying AN and QingChun LI school of Materials Science and Engineering, har.in institute of technology, har.in 150001, china har.in Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China

A continuum model proposed for dendrite solidification of multicomponent alloys, with any partial solid back diffusion, was used to numerically simulate the macroscopic solidification transport phenomena and macrosegregations in an upwards directionally solidified plain carbon steel ingot. The computational results of each macroscopic field of the physical variables involved in the solidification process at a middle solidification stage were presented.

关键词： Simulation Numerical Simulation of Transport Phenomena in Solidification of Multicomponent Ingot Using a Continuum Model

Experimental Study of Bowed-twisted Stators in an Axial Transonic Fan Stage

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Chinese Journal of Aeronautics 2009年第4期22卷 364-370页

作者： Chen Fu,Li Shaobin,Su Jiexian,Wang Zhongqi school of Energy Science and Engineering,har.in institute of technology,har.in 150001,china [a]school of Energy Science and Engineering Harbin Institute of Technology Harbin 150001 China

Bowed-twisted stators with large camber angles have been developed to replace the conventional tandem stators in an axial transonic fan stage working at high subsonic speeds. Experimental study is carried out on both stages with tandem stators and with bowed-twisted stators. Compared to the tandem stators, the bowed-twisted stators change the distribution of the low-energy fluid and the potential high-energy fluid at the compressor outlets, reduce the endwall loss significantly, improve the aerody- namic matching of rotors and stators, and eventually increase the fan stage performances. The aerodynamic performances of the fan stage at different operating points are compared and contrasted. The results show that the transonic fan stage with bowed-twisted stators has better aerodynamic performances. It is thus suggested that the bowed-twisted stators with large camber angles be popularized into the high-loaded transonic fan designs.

关键词： large camber angle bowed-twisted stator aerodynamic performance transonic fan stage

Modeling of the Shape Forming of Composite Roll

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Journal of Materials Science & technology 2000年第3期16卷 337-340页

作者： Chengsong CUI, Zhenyu LI, Fuyang CAO and Qingchun LI (school of Materials Science and Engineering, har.in institute of technology, 150001, china) school of Materials Science and Engineering Harbin Institute of Technology China

A shape modeling of spray formed composite roll, which is utilized to predict the shape and dimension of roll during spray forming process, is developed in this paper. The influences of the principal spray forming parameters, such as the spatial distribution of melt mass flux, spray distance, rotating and translating speeds of substrate bar etc. , on the geometry and dimension of spray formed product were investigated.

关键词： Modeling of the Shape Forming of Composite Roll