Abstract: The solidification structure, central segregation, distribution and type of inclu-sions, microstructure of billets and rolled steel for continuous cast high carbon steel billet-s(150 mm×150 mm), have been investigated and discussed. The proposal of improving the central pore and central segregations of high carbon steel billets has been made.
Abstract: Based on the analysis of the requirement of oxygen supply system for BF oxy-coal process, oxygen supply and safe-control technology is investigated. And inte-grated oxygen supply and safe-control system is developed which can be qualified for safe-guard of individual oxy-coal lance when oxy-coal lance is burnt out or inserted or when the tuyere is inserted. To meet the needs of different blast furnaces, different oxygen supply and safe-control systems are developed, which enable to change initial parameters, to supervise and to control the oxygen supply and safe-control system, to measure and to display the pressures and flow rates of both oxygen and nitrogen.
Abstract: The Zn-Pb-bearing dust from BF and LD dust without Zn were mixed and then made to pellets. The results show that the water content of 21% and time of 20 min, for pellets making were considered to be the best conditions. The compressing strength of moist pellets and dry pellets were 15 N/pellet and 25 N/pellet respectively. The decrepita-tion temperature of moist pellet was 210℃
Abstract: The regularity of the development of inclusions and the cleanliness level of the steel 16MnR during the whole process are investigated. The emphasis is focused on the type, quantity, distribution, sources and formation of the large oxide inclusions in ingot The result shows that the major inclusions in ingot are block Al2O3 The large oxide inclusions mainly come from entrapment of complex slags.
Abstract: The change of concentration of nitrogen in liquid steel has been investigated under the conditions with slag layer and various partial pressure of nitrogen. It is found that neutral and oxidic slags can be as isolators to prevent nitrogen from transport between liquid steel and gas.
Abstract: Computer emulating is developed to represent transport process of stream function, velocity, vorticity, kinetic energy, dissipation rate of turbulence energy, temperature in 75 t DCEAF bath by using vorticity-stream function method and K-ε two equation turbu-lent models. Therefore there is full-scale comprehending for regular pattern of fluid flow and transfer heat process in 75 t DCEAF
Abstract: The construction and application of the distributed computer system for the No. 4 Blast Furnace in Baotou Iron and Steel Corporation were described. The computer system consists of two parts:basic detection and control computers and process computers. The former is responsible for the sampling of real-time signals and the automatic control, while the latter accomplishes the data processing, the operation of expert systems, the prediction of the working status of the BF and the communication among computers.
Abstract: The static state model of steelmaking furnace is made based on the reality data gathered with the kind of Fuzzy Neural Network. The objective temperature of steel and W[C] in steel were calculated by the new model. The results accord with those of measured in the experiment.
Abstract: The dipolar interaction in a mixed two-phase magnet of soft and hard magnetic particles was analysed. It was deduced that the aligned hard magnetic particles exert a positive average magnetic field on the soft magnetic particles, which enhances the coercive force of the soft magnetic phase. This average field along the magnetization direc-tion of the hard magnetic phase is proportional to the volume fraction of the hard phase in the magnet and its saturation magnetization.
Abstract: CVD diamond coating on WC-6%Co for cutting tools has been investigated. The substrates were etched by HCl:HNO3:H3O(volume fraction) 1:1:1 solution at 80℃ for 15min to remove the cobalt from the surface. In order to enhance diamond nucleation, ultrasonic scratching pretreatment was applied by using diamond powder with 40μm parti-cle and the mixture of diamond powder with 1.5μm particle and TaC powder with 20 μm particle. The diamond deposition was performed by the hot filament CVD method.Adhesion was checked using Rockwell hardness machine with a loading capacity of 1 500 N, the experimental results show that the adhesion of CVD diamond coating to WC-6%Co substrate by ultrasonic scratched with diamond powder of 40 μ m particle is better than that of the mixture of diamond powder with 1.5μm particle and TaC powder with 20μm particle.
Abstract: Equations of theoretical calculating distribution coefficients of ions in complex system were analyzed, considering dissociations of the complexants, hydrolizations of metal ions and interactions between complexes at the same time. An optimum and simple calcula-tion method by computer and its program frame were put forward. Distributions of ions in two common complex systems of electroless plating of nickel were extracted.
Abstract: The microstructure of the exploded graphites in cast iron were investigated by using Transmission Electron Microscope and Scanning Electron Microscope. Experimen-tal results show that the exploded graphite is the process in which the growth of the graphite increased. So it does not result from poor nodulizing during the melting of cast iron, but is a kind of graphite with excess nodulizing.
Abstract: Based on the experiment which is made by simulating rolling parameters in site, transformation of formed austenite to ferrite and pearlite related to strain, temperature and cooling rate has been discussed in the paper. The results show that more strain, higher temperature and lower cooling rate can promote, to a different content, the transformation of both ferrite and pearlite from formed austenite.
Abstract: A new concentration transducer for the measurement of gas/solid two-phase flow in the profile of pipeline was studied. The design of grid electrode was employed, and hence the distribute of electric field in the space was homogeneous effectively. The variance of measurement value for the influence of flow regime variations has greatly reduced, and the precision of measurement was improved. Meanwhile, optimization of axial property in the grid electrode increases the ability of tracing and measuring of the concentration signal in real-time.
Abstract: The structure, working principle, measuring circuit and frequency characteristics of contact potential difference nondestructive testing equipment using fixed probe am intro-duced. It is demonstrated by the experimental result that this equipment is effective for testing the local narrow dynamic endurance failure on the surface of metal.
Abstract: Based on the analysis of the process of cross wedge rolling at the first stage wedge in,the geometry model of rolling area has been established. The contact surface equations and boundary curve equations have been deduced. Contact surface of cross wedge rolling in different conditions and stage has obtained.
Abstract: With the aid of XRD,SEM. EDS etc., there is absorbed film on sand grain surface, high temperature modify makes the film sintered firmly on sand grain surface. Thus it changes physical and chemical characteristics of the film and sand grain surface, improves the wetting properties greatly, makes the fracture features of bonding bridge change from the adhesive to the cohesive and raises the strength of sodium sili-cate-bonded sand.
Abstract: On the basis of theory of light and lots of experiments, the proper light wavelength is determined. In the wave band, oil samples imbibe light with general absorp tion, intensity of penetrating light is more stable and higher relatively, variations of oil viscosity have little effect upon ratio of penetrating light,and change of oil color influ-ences ratio of penetrating light.With the Lambert-Beer law combined with the system of single source and double laser-lights, theoretic foundation is inferred for quantitative analy-sis of oil contamination, eliminating influence of oil color and improving accuracy of the device.
Abstract: The dynamics properties of a kind of multi-fingered robot hand is analyzed.It is pointed out that the dynamics property of this kind of multi-fingered robot hand in the approaching process is quite different from that in the grasping process and, different control algorithm should be taken in the two process. A position-force hybrid control algo-rithm is proposed which is applied to the control system of the University of Science and Technology Beijing double-thumb robot hand successfully.
Abstract: The colour reactions of barium (Ⅱ) and strontium (Ⅱ) with dibromomethyl carboxyazo were studied comparatively. In the medium of H3PO4, the colour reaction of barium (Ⅱ) is highly selectivity and tolerates the existence of 6-fold of strontium(Ⅱ). And in the buffer medium of H3BO3-Na2B4O7,the absorbances of colour coordination compounds for barium(Ⅱ) and strontium(Ⅱ) have an additivity over a certain range of concentrtion.On these grounds, a new method of the successive determination for barium and strontium had been developed.
Abstract: Based on the method of system optimization,a production process model is established. An decision making analysis of production process model stability behaviors is conducted using the system control theory and its method. There are enough facts show that using this method costs the system much less time to get stability and makes the productivity more efficiently utilized.
Abstract: Some advanced researches on nonlinear unconstrained optimization problems with variable matrix method (VMM) have been discussed. VMM shows performing satisfac-torily in convergence rate,precisions, computation time and steadiness. As an application example, the element values of a telecommunication line equdizer are searched out by this method.
Abstract: Put forward to establishing the declaring and decision-making system of science and research items in the universities. The system consists the advanced 6 targets of analysis and estimation and devide every target into 3 scales on the informal ton supplied by declaring items. So make certain target proportion and scale demarcation value, then through computer programs transform the target into relevant scale value, systhesiz-ing and marking, and carry out to estabilishing database, optimizing decision-making, demanding, deleting, superaddition, printing, and so on.
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
