Abstract: The change behavior of inner rock mass for combined mining on the basis of analysis of numerical value and actual deformation is explored. Because of effect under combined underground and open pit mining, mechanism about superimposition of deformation and change behavior depends on respectively amount of both mining methods. Deformation of rock mass would more present behavior of underground mining as slope dip angle is small. Therefore, under influence of the same amount in underground excavation, the range and depth of slope deformation are increased as slope dip angle is increased. Both amount of excavation directly influences quantity value and direction of vector. Change of each amount of excavation would make the different behavior of failure and moving mechanism for rock mass is produced.
Abstract: On the basis of the bond betWeen the backfill body of High Water Material and the reinforcing bar, the formula is deduced to calculate the bond strength between above two objects and the simulation model is developed. The conditions of reinforcing and no reinforcing backfill bodys are simulated individually. It is revealed that the mechanism of reinforcement's fracture to the backfill body of High Water Material. The improvement methods are produced at last.
Abstract: A mathematical model was established and applied to simulate the decarburization in RH degasser and to study the effects of [C]0,[O]0, flow amount of Ar and diameter of the snorkels on the decarburization. The results obtained by using the model showed that as considering the RH process in the plant, the oxygen in the melt at the end of decarburization can be reduced by increasing the original carbon and decreasing the original oxygen without unacceptable carbon content. Thus the consumption of deoxidizing alloy can be reduced, and the inclusions produced in deoxidizing process can be reduced.
Abstract: The kinetic process of direct alloying with manganese ore pellets in steelmaking has been studied. The relation of C in initial steel, MnO content in slag, the alkalinity of slag and furnace temperature with reducing rate of MnO in slag during reaction process has been analyzed. The apparent reaction order of MnO reduction is determined as first order reaction. The factors which influence the recovery of Mn and the end point Mn content has been also discussed. The average recovery of Mn is measured as 79.67%.
Abstract: Rolling characteristics of continuous cast slabs with liquid core is studied with the aid of elastic-plastic and thermal-mechanical coupled FEM. The studies show that the longitudinal tensile strain of strand can be ignored for thin shell,but it can not be ignored for thick shell.The effects of shell thickness and related height reduction on the longitudinal tensile strain of strand are analyzed.
Abstract: Different layout of EAF steel plant involves floor space, equipment mass and investment cost etc. The studied results show that different layout is characterized by different ladle transport route and consumed time in essentials, which limit maximum processing time of liquid steel in LF, and affect annual capacity.
Abstract: The electronic characteristics of AC-EAF while smelting was studied. The operation reactance model of AC-EAF was build, and the effects of EAF control parameter β, equipment circuit characteristics γ, scrap conditions and different smelting phases α on the operation reactance were analyzed.
Abstract: At present CALPHAD technique is not capable of predicting even whether there exists intermediate compound and much more predicting nothing about its formula and the number of intermediate compounds. To predict the existence or not, formula and number of intermediate compounds, a new approach called the phase diagram evaluation by pattern recognition (PDEPR for short) has been proposed. The micro-para meters, such as radius and electronegativity of element were used as original features and then they were trans formed and spanned to the different features in multi-dimensional space. Then a set of classifying functions was attained to predict the intermediate compounds in the systems of the REX2-AX (RE:rare earths; A:Li, Na, K, Rb, Cs; X:F, Cl, Br, I).
Abstract: The assessment has been made on several geometric models for ternary systems. The formulas for prediction of activity interaction coefficients have been dirived by ues of a general solution model. The effects of several activity interaction coefficient models have been analyzed and discussed by comparison with experimental values.
Abstract: The performance of temperature is analyzed in the linking region of CSP technology. Firstly, analyses are done on the temperature of the slabs before being charged. pointing out the influence factors, the changing status and the cooling features of the temperature of the slabs in this region. Secondly, researches of the heating of the slabs are done especially on the heating behavior, the heating characteristics, the selecting of models and the requirement on temperature reservation in the heating stage. Finally, the cooling pattern of the slabs in the linking region of CSP is put forward, and the corresponding model presented.
Abstract: A simulation on metal flow rule and stress distribution of non-circular tubes in roll forming process by using 3D large deformation elastic plastic finite element method with considering of material and geometrical non-linearity is presented. This method is based upon Prandtl-Reuss flow ruler and mises yield criterion. The simulation results of grids deformation flow pattern and stress distribution are obtained.
Abstract: The sclerotium of ettringite material is easily effloresced and lower its strength if it is exposed to the air. Its formation and weathering process are studied with methods such as accelerate chemical reaction, X-diffraction, SEM, TG and DT and also its physical chemistry characteristics are expounded. The reason of weathering is that carbon dioxide intrude into ettringite and decompose its structure, and thus loss its strength. This provide the basis for industrialized production and application of ettringite material.
Abstract: The granularity effect for HDDR anisotropy NdFeB powder is studied.The results indicate that the granularity effect for the above powder is low and this powder adapts to preparing for bonded magnet. However, the granularity effect for HDDR anisotropy NdFeB powder is higher than melt-spun NdFeB powder. On the basis of above results, a magnetic powder defect layer model is put forward. The model considers that each magnetic powder consists of surface defect layer, transition layer and main body and that the overall magnetic properties of each magnetic powder result from the magnetic properties of the above each layer of the magnetic powder.
Abstract: The influence of preheat temperature to the size of primary Si phrase of hypereutectic Al-Si X alloy produced by Spray-forming is concerned, the materials' microstrucature which extruded under the same temperature but different extrusion ratio are compared. The various effect of atomizing gas to melting metal and extrusion ratio to the primary Si phrase are discussed and the possible reasons which might cause microcracks are analyzed.
Abstract: A finite element numerical model has been developed to describe the temperature distribution of slab in coiler furnace. The results of numerical simulation using ANSYS software agree with the practice. It is helpful for drawing reasonable procedure of the process.
Abstract: The stress fields of bolted glass curtain wall under the action of wind load were studied by means of finite element method and the features of the stress fields were discussed. Calculation formula of the maximum deflection of bolted glass was obtained. The results of calculation by the formula were in correspondence with the experimental data.
Abstract: Aluminium alloy or steel is joined to ceramics using inorganic adhensive bonding. Phenomenon occurring in experiments and factors effecting the strength of bonding were emphatically analysed. It was found that expansion coefficient was not the important factor that effected the strength of dado joint of steel to ceramics.
Abstract: The problems of GB5213-85 in evaluation of stamping grade were discussed and the correlation of basic formability and simulative formability was analyzed. According to the forming classification of punch-formed car components, the new method for evaluating stamping grade was put forward.
Abstract: With the help of commercial finite element software MARC/Autoforge, angle steel rolling process using large strain elasto-plastic coupled thermo-mechanical finite element method was simulated. The problems of metal deformation, temperature field and spread were analysed and key point was placed to distribution of deformation and stress in rolling process. Simulation results compared with rolling practice which shows numerical simulation is good agreement with rolling practice.
Abstract: Thermal stability and interface diffusion of Si/Ta/NiFe/Cu/NiFe/FeMn/Ta spin-valve have been investigated. The columnar grains are observed by high resolution electron microscopy (HREM). The pinning field increases when annealing temperature is lower than 200℃; when the annealing temperature is higher than 200℃, the pinning field decreases and other properties deteriorates; at 300℃ the pinning field will be zero. From the results of Auger electron spectroscopy(AES), it can conclude that the diffusion among layers is mainly along grain boundary when the annealing temperature is lower than 200℃. The effect of bulk diffusion should be considered at 300℃.
Abstract: A new method for further frequency analysis whose name is wavelet-cepstrum is established. The method of IMMS(Integrated Monitoring by Statistic Parameters in Multiple Scale) based on wavelet-cepstrum analysis is applied to condition monitoring of microbore drilling and the results are satisfactory.
Abstract: The measurement system to calculate the volume of the stockpiles by using computer-aided measuring technique is introduced. This system includes taking photos of the stockpile on the spot and scanning the photos into images in the computer to do 3-D reconstruction and volume calculation. In the part of volume calculation, offers in detail a complete set of algorithms which has eight procedures including filtering raw data, constructing triangle grid, computing interpolation points on the contours, searching contours, judging the relationships among contours, fitting contours and calculating contour' area and stockpile's volume. Based on these algorithms, a volumetric calculation subroutine is developed. By measuring a real coal pile, the feasibility and validity of these algorithms is tested well.
Abstract: The possibility of monocular vision system put into use on moulds level measuring in continuous casting steel is researched. Based on hardware configuration, corresponding software has been developed. The experiment has been done, the result is fesaible.So an new solution to measure moulds level in continuous casting steel is proposed.
Abstract: A discrete time direct adaptive control algorithm is proposed, which not only remains the features of simple adaptive control but also obeys the causation between input and output for computing the control law. The algorithm also can directly force the plant output to follow the output of the idea model. Lyapunov function and positive real lemma are used to prove the stability of the algorithm. Finally, an example is simulated to confirm the validity of the algorithm.
Abstract: The intelligent control principle is used in measurement of looper angle, looper rise and down control. In addition,the fuzzy controller is used in close loop control of looper height. The milling speed self modification and compensation method of dynamic speed drop are given.
Abstract: By applying permutation group theory,the concepts of hyperedge group, hypergraph group and hypergraph isomorphism are introduced, and the general expressions of hyperedge group and its cycle index are derived. Then the counting series are derived for undirected unlabeled and labeled hypergraphs, thus the isomorphism and counting problems of undirected hypergraphs are solved.
Monthly, started in 1955 Supervising institution：Ministry of Education Sponsoring Institution：University of Science and Technology Beijing Editorial office：Editorial Department of Chinese Journal of Engineering Publisher：Science Press Chairperson：Ren-shu Yang Editor-in-Chief：Ai-xiang Wu ISSN 2095-9389CN 2095-9389
