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Mining Science and Technology 2010年第6期20卷 904-907页

作者： XIE Fangwei, HOU Youfu school of mechanical and electrical engineering, china University of Mining & Technology, Xuzhou 221008, china [a] school of mechanical electrical engineering China University of Mining & Technology Xuzhou 221008 China

To show the distribution of a temp.r.ture field on a steel disk and to prolong the service life of a friction pair in a Hy-dro-Viscous Drive (HVD) device, a theoretical model of a transient temp.r.ture field was established, based on the theory of heat conduction. This theoretical model was solved using a finite element method. The results show that the surface temp.r.ture of the steel disk does not increase consistently as a function of the radius; the highest temp.r.ture appears short of the maximum radius. The relationship between the surface temp.r.ture and the mixed friction time is exponential. With a friction time of 15 s, the tem-p.r.ture reached 465.9 °C. Simultaneously, the internal thermal stress is larger than the yield stress of the material, causing a warping deformation of the steel disk. The largest axial deformation is 0.32 mm. The results of the exp.r.ment suggest that the de-formation is the same as that obtained from numerical simulation. Therefore, deformation of the steel disk must be considered dur-ing the study of the characteristics of a HVD.

关键词： hydro-viscous steel disk temp.r.ture field deformation numerical simulation

Effect of prep.r.tion Methods on mechanical prop.r.ies of pVA/HA Composite Hydrogel

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Journal of Bionic engineering 2010年第3期7卷 235-243页

作者： Dekun Zhang~1, Junjie Duan~1, Dagang Wang~2, Shirong Ge~2 1. school of Materials Science and engineering, china University of Mining and Technology Xuzhou 221116, p. r. china 2. school of mechanical and electrical engineering, china University of Mining and Technology, Xuzhou 221116, p. r. china [a] school of Materials Science engineering China University of Mining Technology Xuzhou 221116 P. R. China [b] School of Mechanical electrical engineering China University of Mining Technology Xuzhou 221116 P. R. China

poly(vinyl alcohol) (pVA)/hydroxyapatite (HA) composite hydrogel specimens were prep.r.d with 15% pVA and 1%,2%, 3%, 4% and 5% HA by repeated freezing-thawing. The tests of static and dynamic mechanical prop.r.ies were carried out todiscuss the influence of different contents of HA and freezing-thawing cycles on the mechanical prop.r.ies of pVA/HA compositehydrogel. The results of static mechanical tests showed that the pVA/HA composite hydrogel with 3% HA and ninefreezing-thawing cycles had excellent stress relaxation prop.r.ies, higher relaxation ratio, lower stress equilibrium value andpresented better prop.r.ies of creep and recovery. The results of dynamic mechanical test showed that the pVA/HA compositehydrogel with nine freezing-thawing cycles had higher storage modulus and loss modulus, so was the pVA/HA compositehydrogel with 3% HA.

关键词： composite hydrogel HA contents freezing-thawing cycles static prop.r.ies dynamic prop.r.ies

A New Measurement Method for Unbalanced Moments in a Two-axis Gimbaled Seeker

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Chinese Journal of Aeronautics 2010年第1期23卷 117-122页

作者： Yu Shuang,Zhao Yanzheng school of mechanical engineering,Shanghai Jiaotong University,Shanghai 200240,china [a] school of mechanical engineering Shanghai Jiaotong University Shanghai 200240 China

This article presents a novel method to measure unbalanced moments in a two-axis gimbaled seeker commonly believed to seviously influence the tracking accuracy and stabilizing capability. This method enables individual measurement of unbalanced moments, and judgment of the seeker＇ s status-balanced or not. Furthermore, an instrument is designed based on this method and calibrated. The effectiveness of the proposed method is validated through a simulation. The exp.r.mental results show a satisfied level of accuracy the measurements have. This work forms a basis for the further development of a more stabilized gimbaled seeker with less induced vibration and consumed power.

关键词： gimbaled seeker weight sensors measurement unbalanced

TiC/Fe cermet coating by plasma cladding using asphalt as a carbonaceous precursor

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progress in Natural Science:Materials International 2008年第4期18卷 447-454页

作者： Junbo Liu school of mechanical and Electronic engineering, Weifang University, Weifang 261061, china school of mechanical and Electronic engineering Weifang University Weifang 261061 China

A new Ti-Fe-C compound powder for plasma cladding was prep.r.d by heating a mixture powder of ferrotitanium and asphalt p.r.-lyzed as a carbonaceous precursor. The carbon by the p.r.lysis of the asphalt acts as a reactive constituent as well as a binder in the compound powder. The TiC/Fe cermet coatings were prep.r.d by plasma cladding with the compound powder. results show that the Ti-Fe-C compound powder has a very tight structure, which can avoid the problem of the reactive constituent p.r.icles being sep- arated during cladding. The TiC/Fe cermet coating presents a typical morphology of plasma cladding coatings with two different lam- inated layers:one is the composite layer in which the round fine TiC p.r.icles (re disp.r.ed within a Fe matrix, the other is the p.r.gentic layer of TiC and Ti2O3. The coating shows high hardness and excellent wear resistance. The surface hardness of the coating is 68 ± 5(Hr30N). In the same fretting conditions, the wear area of Ni60 coating is about 11 times as much as the TiC/Fe cermet coating.

关键词： plasma cladding TiC/Fe cermet coating precursor Microstructure Wear resistance

Cutting tool materials for high speed machining

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progress in Natural Science:Materials International 2005年第9期15卷 777-783页

作者： LIU Zhanqiang** and AI Xing(school of mechanical engineering, Shandong University, Jinan 250061, china) school of mechanical engineering Shandong University Jinan 250061 China

High speed machining (HSM) is one of the emerging cutting processes, which is machining at a speed significantly higher than the speed commonly in use on the shop floor. In the last twenty years, high speed machining has received great attentions as a technological solution for high productivity in manufacturing. This article reviews the developments of tool materials in high speed machining op.r.tions, and the prop.r.ies, applications and prospective developments of tool materials in HSM are also presented.

关键词： tool materials high speed machining.

A New Genetic Algorithm Based on Niche Technique and Local Search Method

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Journal of University of Science and Technology Beijing 2001年第1期8卷 63-68页

作者： Jinwu Xu, Jiwen Liu mechanical engineering school, University of Science and Technology Beijing, Beijing 100083, china Univ Sci & Technol Beijing Sch Mech Engn Beijing 100083 Peoples R China

The genetic algorithm has been widely used in many fields as an easy robust global search and optimization method. In this pap.r. a new generic algorithm based on niche technique and local search method is presented under the consideration of inadequacies of the simple genetic algorithm. In order to prove the adaptability and validity of the improved genetic algorithm, optimization problems of multimodal functions with equal peaks, unequal peaks and complicated peak distribution are discussed. The simulation results show that comp.r.d to other niching methods, this improved genetic algorithm has obvious potential on many respects, such as convergence speed, solution accuracy, ability of global optimization, etc.

关键词： genetic algorithm (GA) niche technique local search method

research of Digital Manufacturing Technology Application on Ultra-precision Optical Workpiece Machining

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武汉理工大学学报 2006年第S1期28卷 359-362页

作者： HE Daxing (school of mechanical and electrical engineering,Wuhan University of Technology,Wuhan 430070,china) school of mechanical and electrical engineering Wuhan University of TechnologyWuhan 430070China

Digital manufacturing technology can be used in optical field to solve many problems caused by traditional machining. According to the characters of digital manufacturing and the practical applications of ultra-precision machining,the process of digital ultra-precision machining and its technical contents were presented in this pap.r. In the conclusions,it was stated that the digitalization of ultra-precision machining will be an economical and efficient way for the production of new sorts of optical workpieces.

关键词： digital manufacturing ultra-precision machining technology optical application

Analysis on Tribological prop.r.ies of potentially New Friction Material with response Surface Method

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Journal of Wuhan University of Technology(Materials Science) 2011年第3期26卷 499-503页

作者：徐蕾 school of mechanical and electrical engineering China University of Mining & Technology

The tribological prop.r.ies of newly developed friction material were evaluated by statistical analysis of the major affecting *** material for investigation was non-metallic friction material synergistically reinforced with aramid fibre and CaSO 4 whisker,which was developed for hoisting applications in coal *** response surface method（rSM）was employed to analyze the material p.r.ormances affected by the independent and interactive effect of the factors under the normal working condition and severe working condition,*** showed that under the normal working condition,the newly developed material exhibited stable tribological prop.r.ies which were insensitive to the test *** under the severe working condition,the sliding velocity was the most dominant factor affecting the friction ***,comp.r.d to the commercially available material,the modified material showed sup.r.or wear resistance and thermal stability.

关键词： tribological prop.r.ies friction material response surface method wear

The Influence of Some Key p.r.meters on Fatigue Life of Common Metallic Components

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Journal of Central South University 2000年第3期12卷 159-161页

作者： LIU Yi lun (College of mechanical and electrical engineering, Central South University, Changsha 410083, china) 1. College of mechanical and electrical engineering Central South University 410083 Changsha China

The effect of key p.r.meters on fatigue life of common metallic components, e.g. steel, aluminium alloy, has been analysed quantitatively. The influential coverage and degree of these p.r.meters have been investigated systematically, some phenomena which can′t be discovered with qualitative analysis method have been revealed, a series of valuable conclusions has been obtained, which would be very beneficial to fatigue resistant design and improvement of anti fatigue ability of metallic components.

关键词： metallic material component fatigue life key p.r.meter effect