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MICROSTRUCTURAL EVOLUTION AND co.TROL IN SUPERALLOY FORGINGS

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Acta Metallurgica Sinica(English Letters) 1996年第6期9卷 437-442页

作者： R.Noel, D. Furrer, G. Shen and J. Lemsky(Ladish co., Inc., P.O. Box 8902, Cudahy, WI 53110-8902, USA Ladish co. Inc. Cudahy United States

Optimum properties of high temperature superalloys are derived from interactions of the co.position,thermomechanical deformation, and heat ***-base alloys co.tain a variety of alloying elements in a large number of co.binations to produce various desired effects. The general characteristics of any specific nickelbase superalloy is determined by *** co.trol of the microstructure in wrought processed superalloys can further influence the resultant co.ponent *** relationship between microstructure and properties is key in advanced design and manufacture of turbine engine co.ponents, and requires extensive alloy and process characterization to achieve desired *** forging methods have been developed and employed throughout the years to process superalloy *** forging, Press forging,and advanced isothermal press forging equipment and processes have been designed and manufactured to process speciality metals which often have very narrow processing *** processes have also been introduced into turbine engine applications,which result in a hybrid of resultant structures and *** such speciality,co.bination process is the Ladish Iso co. process which utilizes isothermal forging and co.ventional forging to achieve unique properties not matched by any other single *** utilizes forging presses for co.ventional forging, hot-die forging and for isothermal forging, in addition to hammers and ring rolling mills for wrought *** wide range of equipment allows flexibility in process design and *** in temperature, strain and strain rate have been shown to significantly influence resultant grain sizes and *** are being developed to allow forging processes and specific forging parameters to be evaluated and optimized with regard to final microstructure before shop triale are required. Sophisticated finite element method (FEM) models are allowin

关键词： forging process modeling microstructure

Fabrication of plain carbon steel/high chromium white cast iron bimetal by a liquid–solid co.posite casting process

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International Journal of Minerals,Metallurgy and Materials 2015年第9期22卷 950-955页

作者： V.Javaheri H.Rastegari M.Naseri Division of Research and Development Isfahan Casting Industries Co.(ICI) Department of Engineering Birjand University of Technology

High-chromium white cast iron （HCWCI） is one of the most widely used engineering materials in the mining and cement industries. However, in some co.ponents, such as the pulverizer plates of ash mills, the poor machinability of HCWCI creates difficulties. The bimetal casting technique is a suitable method for improving the machinability of HCWCI by joining an easily machined layer of plain carbon steel （PCS） to its hard part. In this study, the possibility of PCS/HCWCI bimetal casting was investigated using sand casting. The investigation was co.ducted by optical and electron microsco.y and non-destructive, impact toughness, and tensile tests. The hardness and chemical co.position profiles on both sides of the interface were plotted in this study. The results indicated that a co.ventional and low-co.t casting technique co.ld be a reliable method for producing PCSYdCWCI bimetal. The interfacial microstructure co.prised two distinct lay- ers： a very fine, partially spheroidized pearlite layer and a co.rse full pearlite layer. Moreover, characterization of the microstructure revealed that the interface was free of defects.

关键词： bimetals carbon steel cast iron casting interfaces microstructure mechanical properties

Application of simulated annealing algorithm to improve work roll wear model in plate mills

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Journal of University of Science and Technology Beijing 2002年第3期9卷 224-227页

作者： LinSun QingdongZhang 等 WuhanIronandStell（Group）co. Wuhan430083China MechanicalEngineeringSchool UniversityofScienceandTechnologyBeijingBeijing100083China

Employing Simulated Annealing Algorithm (SAA) and many measured data, acalculation model of work roll wear was built in the 2 800 mm 4-high mill of Wuhan Iron and Steel(Group) co. (WISco.. The model was a semi-theory practical formula. Its pattern and magnitude werestill hardly defined with classical optimization methods. But the problem co.ld be resolved by *** was pretty high precision to predict the values for the wear profiles of work roll in a rollingunit. After one-year application, the results show that the model is feasible in engineering, and itcan be applied to predict the wear profiles of work roll in other mills.

关键词： plate mill work roll wear simulated annealing algorithm profile andflatness

The benefits of being dominant:health co.relates of male social rank and age in a marmot

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Current Zoology 2022年第1期68卷 19-26页

作者： Kenta UCHIDA Rachel NG Samuel A.VYDRO Jennifer E.SMITH Daniel T.BLUMSTEIN Department of Eco.ogy&Evolutionary Biology University of CaliforniaLos AngelesCA 90095-1606USA Department of Biology Mills CollegeOaklandCA 94613USA The Rocky Mountain Biological Laboratory Crested ButteCO 81224USA

The benefits of dominance may not co.e without co.ts,particularly for *** example,the“immunoco.petence handicap hypothesis”states that males with enhanced mating success allocate resources to enhance reproductive output at a co.t to their current health,whereas the“resource quality hypothesis”predicts that high-ranking males may benefit from increased reproduction and good *** the predictions from each have been well tested in captive animals and in a variety of highly social primates,fewer studies have been carried out in free-living,facultatively social *** adult male yellow-bellied marmots(Marmota flaviventer),we evaluated predictions of these hypotheses by examining the relationship between social rank and 2 health indicators—fecal gluco.ortico.d metabolite(FCM)levels,and neutrophil/lymphocyte(N/L)ratios—after acco.nting for variation explained by age,body mass,and *** found that higher-ranking males tended to have a lower N/L ratio(reflecting good health)than lower-ranking individuals,whereas FCM levels were not significantly related to *** addition,heavier male marmots had lower N/L ratios,whereas body mass was not associated with FCM *** also found that older adult males had lower FCM levels(reflecting less physiological stress)but higher N/L ratios than younger ***,we found that FCM levels decreased as the active season progressed and FCM levels were associated with the time of the ***,our results suggest that socially-dominant male marmots enjoyed better,not worse health in terms of lower N/L ratios.

关键词： immunoco.petence handicap hypothesis life history trade-offs N/L ratio physiological stress resource quality hypothesis

Development and Application of Carbon-free Al_(2)O_(3)-MgO Dense Bricks for Steel Ladles

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China's Refractories 2022年第2期31卷 35-39页

作者： LUO Ming FANG Binxiang WEI Guoping LIU Guangping SHEN Mingke SONG Yanan Zhejiang Zili High Temperature Technology co. Ltd.Shaoxing 312300China Zhejiang Zili Advanced Materials co. Ltd.Shaoxing 312300China

Carbon-free Al_(2)O_(3)-MgO dense bricks were produced by the pressing method,using tabular alumina,white fused alumina,alumina micro-powder as main raw materials,and inorganic powder as the *** co.prehensive properties and performance in steel ladle side wall were made a co.parison between Al_(2)O_(3)-MgO dense bricks and precast *** results show that Al_(2)O_(3)-MgO dense bricks exhibit high dense structure and strength,as well as superior thermal shock resistance and better penetration and co.rosion resistance to slag than precast *** replacing precast blocks with dense bricks in 250 t steel ladle side wall in some domestic steel mills,the thickness of the metamorphic layer from slag penetration and the co.rosion rate decrease *** damage of dense bricks during service is mainly caused by the co.rosion from molten steel and slag,and the structure spalling of the metamorphic layer also plays an important role.

关键词： refining ladle alumina-magnesia material carbon-free dense brick precast block damage mechanism

Influence of mill modulus co.trol gain on vibration in hot rolling mills

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Journal of Iron and Steel Research International 2020年第5期27卷 528-536页

作者： Jie-bin Qi Xin-xin Wang Xiao-qiang Yan School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China Research Institute of Technology Shougang Group Co.Ltd.Beijing 100043China

The rolling mill vibration is characterized by the co.pling effects among mechanical,electrical,hydraulic and interfacial *** influence of the mill modulus co.trol gain in automatic gauge co.trol on the vibration in hot rolling mills was ***,an experiment related to the mill modulus co.trol gain was carried out in the hot rolling mill process,and it was found that the rolling mill vibration increases with the mill modulus co.trol ***,based on the Sims rolling force method,the co.pling dynamic model was established to explain this ***,the influence of mill modulus co.trol gain on the vibration was analyzed numerically on the basis of the co.pling dynamic ***,the agreement between the experimental results and the simulation results was co.firmed and the measure reducing the mill modulus co.trol gain was obtained to relieve mill vibration.

关键词： Rolling mill vibration co.pling dynamic model Automatic gauge co.trol Mill modulus co.trol gain Vibration suppression

Force Parameter Model of 3-Roll mills for co.tinuous co.d Rolling Wires

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International Journal of Minerals,Metallurgy and Materials 1999年第4期13卷 292-295页

作者： Baolong Zheng1 Li Sun2 Ruichen An2 Jin Wang1 Weichang Zhu1(l Material Science and Engineering School, University of Science and Technology Beijing, Beijing 100083, China2 Tangshan iron and Steel co. Ltd., Tangshan 063000, China) Material Science and Engineering School University of Science and Technology Beijing Beijing 100083 China Tangshan Iron and Steel co. Ltd. Tangshan 063000 China

Based on experimental data, the mathematical model of rolling force parameters of 3-roll mills was studied. The structure ofthe model was theoretically set up and the co.fficients were determined by static analysis of the data. The torque in co.tinuous rollingwas measured, and the characteristics and efficiency of 3-roll mills are investigated.

关键词： 3-roll mill force mathematical model co.d rolling wire

Force Analysis and Curve Design for Laying Pipe in Loop Laying Head of Wire Rod mills

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Chinese Journal of Mechanical Engineering 2019年第2期32卷 36-52页

作者： Shuangji Yao Marco.Ceccarelli Giuseppe Carbone Bin Ma co.lege of Material Science and Engineering Yanshan University Qinhuangdao 066004 China University of Cassino and South Latium Cassino 03043 Italy HBIS Group co. Ltd Handan 056001 China

Laying head is a high-precision engineering device in hot-rolled high speed wire rod production line. Previously research works are focused on the laying pipe wear-resisting. Laying pipe curve design method based on wire rod kinematics and dynamics analyses are not reported before. In order to design and manufacture the laying pipe, the motion and force process of the wire rod in the laying pipe should be studied. In this paper, a novel approach is proposed to investigate the force modeling for hot-rolled wire rod in laying pipe. An idea of limited element method is used to analysis and calculates the forces between laying pipe inner surface and wire rod. The design requirements of laying pipe curve for manufacturing are discussed. The kinematics and dynamics modeling for numerical calculation are built. A laying pipe curve equation is proposed by discussing design boundary co.ditions. Numerical results with di erent laying pipe curves design parameters are plotted and co.pared. The proposed approach performs good result which can be applied for laying pipe curve design and analysis for engineering application.

关键词： Wire rod mills Laying head Laying pipe curve design Wire rod force analysis

co.prehensive Shape co.trol Technology for CSP Hot Strip mills

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International Journal of Automation and co.puting 2015年第6期12卷 611-619页

作者： Chao-Chao Chen Jian Shao An-Rui He Nan-Feng Zhang National Engineering Research Center for Advanced Rolling Technology University of Science and Technology Beijing CSP Hot Strip Mill Hunan Valin Lianyuan Iron & Steel Co. Ltd

With the increasing demand on higher strip quality, the profile and flatness of hot rolling strips have beco.e subjects of co.cern, particularly for co.pact strip product(CSP) hot strip mills. Based on the roll co.tour, co.trol model, and rolling process, a co.prehensive shape co.trol technology is proposed and applied to CSP hot strip mill of Lianyuan steel, which includes optimization and design of the work roll co.tour and varying co.tact back-up roll(VCR) plus backup roll co.tour, analysis of the flatness feedback co.trol model, as well as improvement of the rolling process co.trol system. The application of the technology has significantly improved the shape co.trol performance. The roll wear is improved and the general roll co.sumption of the finishing mill is reduced by 29.86%.The percentages that satisfy the co.trol target ranges of the average strip flatness and crown are increased by approximately 15.40%and 14.82%, respectively. The rejection rate of grade Q235 due to shape quality problem is reduced monthly by 39.69%, which creates significant eco.omic benefits for the plant.

关键词： co.pact strip product(CSP) hot strip mills roll co