Abstract: Smelting to local condition can be used for full application of chine-se poor manganous ore, and this process probably provides a new variety of B.F ferro-alloy. This industrial experiment was based on therotical investigation and carried out with a small B. F. of 36m3. The test shows that the smelting Si-Mn ferro-alloy of 12-14% Si content in blast furnace with oxygen enriched blast is success technically and beneficial economically in Chinese condition.
Abstract: This paper analyzes the importance of measuring heat tranfer coefficient in continuous casting in theory and sets out the way to calculate heat transfer coefficient and to design the apparatus. It consists of heating and controlling temperature system. It can amplify and collect the signal system, calcaulate and type the results of system, etc. There is a 8 bit micro-computer and micro-typcr in it.The process,from heating the probe to typing the result, can be done automatically. The measurement was made for many times in same conditions and the results were stable and reliable.
Abstract: This paper discusses the conditions of translation from a thermally wall body into a thermally thin body, the former the temperature is both functions of time and space, the later the temperature is single function of time under connective heat tranfer circumstance. On the bases of analysing the reasonableness and limitation of all criteria of thin wall body at present, a new criterion of thin wall body has been developted, in which the largest dimensionless temperature gradient is considered less than a certain constant, and the effect of Fo and Bi numbers on the new criterion has also been demonstrated.
Abstract: In this work,it is proved experimentally and theorically that the speed grade of the dual motors differential drive continuous rolling system is very good, it can fully meet the requirements of the continuous rolling technique. This advanced technique developed in our country is of good performance and can be used in building the continuous rolling mill adaptively and economically.
Abstract: The influence of some main working parameters——area reduction,die angle and friction coefficient on deformation procss is calculated and analysed during the hydrostatic extrusion of bar. Workhardening is also considered.The results of calculation are approximately in agreement with those of experiment.
Abstract: Experiments have been made on 16Mn steels with various contents of carbon, silicon and manganese under the condition of controlled rolling and controlled cooling. We have now measured their various mechanical properties and have made quantitative metallographic analyses for their major structural parameters such as the average diameters of their ferrite grains (dF) and pearlite percentages(Pe%). We have made multelinear progressive regressive analyses to find out the relationships between their various mechanical properties and the contents of different elements in 16Mn steels as well as their two main structural parameters.As a result, We have obtained th formulas of quantitative relationships between the various mechanical properties of controlled rolled and controlled cooled 16Mn Steels and theire chemical compositions and structural parameters. According to the informations provided by these formulas,and referring to the mttltilinea regressive equations of the two structural parameters to the chemical compositions of steels and their technological parameters of controlled rolling and controlled cooling, we probed into the strenthen-toughening mechanism of controlled rolled and controlled cooled 16Mn steels.
Abstract: The influence of stress rupture notch sensitivity on crack growth rates have been investigated in GH36 iron-base superalloy discs.Stress rupture ductility improvement can eleminate stress rupture notch sensitivity and decrease the crack growth rates under creep condition or where creep is the dominant failure mode. But under fatigue condition, the crack growth raets are sensitive to material strength and independent of stress rupture notch sensitivity.Material strength improvement can significantly increase the resistance to low cycle fatigue crack growth.In order to improve the resistance to crack growth under creep, fatigue and creep/fatigue interacton, materials should be improved in both strength and ductility.
Abstract: The present work has found that the transverse rupture strength of WC-Co hard metals can be improved by quenching heat treatment. The icrement of transverse rupture strength(TRS) is dependent on the cobalt content of hard metal.The higher the cobalt content of hard metal is,the more the increament of transverse rupture strength is. The main rea son is that the transformtion of face centered cubic cobalt stable at high temperature to hexagonal closepacked can be depressed by quenchin g heat treatment.The transformation temperature increases with the increase of cobalt content of hard metal by means of differential thermal anaysis because binder phase of high cobalt hard metal contains higher tungsten content than that of low hard metal during reheating.
Abstract: A corrected Miner hypothesis has been developed to overcome an obvious defect in Miner hypothesis. The authors, based on this, give out the calculating formulas of the equivalent loads for machine elements which bear different kind of variable loads and put forward some requirements to use it correctly. A practical example of equivalent load is calculated and its result is examined by test. It shows that the formulas are possessed of certain accuracy and may be used in practical engineering.
Abstract: This paper presents a new recursive algorithm of robot dynamics based on the Kane's dynamical equation.The algorithm is simple and illustrative,and can be used for solving dynamic problem of robots containing closed-chain without cutting the closed-chain open. Also, it is especial available to CAD of robot because it can be easily realized on computer.In the end of the paper,an example of computation of dynamics of robot with 2-DOF and one closed-chain is given to demonstrate computing stages and methods of establishing dynamic equation of robot using the new algorithm.
Abstract: It is known that the state space for time-invariant linear system can be decomposed into different canonical forms with regard to its controllability and observability.In this paper proposes four decomposition methods which leads the state space up to an unit and easy-calculated canonical form, and also give an example to show how to use the methods and some comments on some problems related to.
Abstract: A temperature controlling process of the electric furnace by means cf the fuzzy control is proposed in this paper.The process consists of three stages of temperature by time. Elevated,invariable and cooling rapidly. Each stage of temperature can be controlled by the track of temperature using toe fuzzy control. A simlifed fuzzy control alogrithms is also put forward.
Abstract: The graphic methods for calculating ${{\rm{\bar G}}_2}$ and ${{\rm{\bar G}}_}$ from the known ${{\rm{\bar G}}_1}$ (${\rm{\bar G}}$i is the partial molar property of ith component) are systematically discussed with emphasis on the indirect methods following the way ${{{\rm{\bar G}}}_1} \to {\rm{\bar G}}$ or ${\rm{R(R=}}\frac{{\rm{G}}}{{1-{{\rm{x}}_1}}}{\rm{)}} \to {{{\rm{\bar G}}}_2}$ and ${{{\rm{\bar G}}}_3}$. An new and simple way of de-riving Darken's and Chou's equations based on the efficient uses of fun damental thermodynamic relationships is proposed, which shosvs clearly the close links between two methods, the significances of introducing R and y (y=x3/(x2 +x3)) in Chou's equations, and the main points of the indirect methods.It is theoretically concluded that Chou's method developed from and perfected Darken's method and is a good method for graphic calculations of thermodynamic properties of ternary systems. Moreover, this paper presents two criteria for verifying respectively the reliability of experimental data and calculated results in ternary systems from the known data in the related binary systems.
Abstract: This paper reports the new technology which improves the corrosion resistance of transtor leads by compositive gold plating. A plating system consisting of dark nickel, Ni-Al2O3 compositive plating and acidic pulse gold plating is plated on Kovar leads. The porous gold plating system decreases the tendency of corrosion fracture distinctly.
Abstract: A high-grade Zn-Fe alloy coating containing 16-17 wt% Fe can be obtained by electroplating in the plating solution consisting of sulfate solution. The micrograph of this coating has found η phase, δ1 phase, Y phase and a phase.Hm=803.6-891.8MPa.
Abstract: The present paper describes the charecteristics of Barkhausen noise and magnetomechanical acoustic emission in ferrite-martensite dualphase steels during Barkhausen jumps, and the influence of mic-rostrcture, stress and strain on a magnetic and acoustic Barkhausen signal.The results show that Barkhausen noise(BN) in dual phase steels strengthen with the increase of the pulling stress,and that weaken with the decrease of comprassive stress.The relationship between Barkhausen signal and the mechanism of deformation in materials is discussed.
Abstract: V-bearing stone coal is a new kind of vanadium resource.The oxids tion states of vanadium in the Chong Yang stone coal were analyzed by means of electroanalysis and mineral separation, the result shows that it contains 98.77% of V (Ⅲ) and 1.23% of V (Ⅳ).neither V (Ⅱ) nor V (Ⅴ).The distribution of oxidation states of V shows that both organic matter and pyrite could prevent V (Ⅲ) from oxidizing to V (Ⅳ),below 400℃,the oxidation states of V are mainly dependent upon reducing minerals, but over 400℃, the temperature is the most important factor. At about 520℃, V (Ⅲ) is completely oxidized into V(Ⅳ):at 700-1000℃ 82% of V in the stone coal are oxidized into V(Ⅴ), over the range of high temperature no more V is oxidized into V(Ⅴ), an equilibrium, between V (Ⅳ) and V (Ⅴ) is established.Salt roasting may play very important role in extracting V from the stone coal,from the results of our experiment it is considered that NaC1 can not only promote the oxidation of V, but also react with V to form soluble vanadate.The best conditions for roasting are temperature 775℃ for 15 minutes and mineral:salt=100:10 by weight, η reaches 81%.
Abstract: We have compared the sensitization of various sensitizers to the coloration of chromium (Ⅲ) with chrome azurol S, and have considered to utilize the kinetic inert character of chromium complex in order to enhance the selectivity of the color development reactions.In this paper,a new sensitized multicomponent complex in the system of "Chromium (Ⅲ)——Chrome azurol S——Alkyl dimethyl amino acetai cacid"have been developed. The optimum condtions for the formation of the complex in this system have been studied.It was proved that the bromide of cetyl dimethyl amino acetic acid(CDMAA) or tetradecyl dimethyl amino acetic acid (TDMAA) is more suitable to be used as a sensitizer in the spectrophotometric determination of microamount of chromium with high sensitivity and selectivity. When CDMAA or TDMAA is used as sensitizer the molar absorptivity is 1.56×105 or 1.88×105 respectively.The sensitization of these two sensitizersare higher than all these sensitizers which had been reported formerly.
Abstract: The distribution of friction is studied, when the contact area between a body and stationary plane is a cycle. This method is based upon the concept of transiant rotation center.The equilibrium condition is obtained, based on the hypothesis that the rotation center is in (on)/outside the contact cycle.A series of parameter values are given.
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
