Abstract: A method for output of crude steel prediction using grey system theory is described. This prediction model consists of ration and qualitative anlysis. The qualitative prediction is 97.08% in an average of exact percentage (the most of exact percentage is 99.60%). The ration prediction is the same results with the practical case.
Abstract: The machanism of whirl burning of the eddycrust swirlcr powder coal burner has been analysed. The coal burner has the advantage of the higher capture, higher carbon burnout, higher volume heat flux and lower pollution. The whirling velocity formulae of the viscosity eddy in the coal burner, the velocity distribution in the cold test under the condition of the secondary tuyere notch leaning backward, the heating power calculating are also introduced.
Abstract: Analyse and compare all kinds of models of I-beam flange demen-sions. The models of flange high strech and shrink have been made by the model test. Also, a few ways of finishing functions of I-beam CARD program system have been discussed.
Abstract: This paper discusses how to display the overlapping graph of the shape of the stock section and the pass on the screen, how to solve some particular questions when display the graph on the screen, how to realize the programming overlay and their adventages.
Abstract: The constituent and the structure of the interface layer between the low temperature deposited diamond films and the single crystal silicon substrate was studed by X-ray diffraction (including small angle diffraction) technique. It was found that the interface layer for diamond film deposited at 700℃ was α-SiC. At lower temperature range (580-290)℃, the interface layer was composed of α-SiC and SiO2. Crystal structure of α-SiC and SiO2, and the d-spacings of the diamond films were discussed.
Abstract: The two phases microstructure of dual phase steel produced by induction heat treatment and duplex quench processing is investigated. The results show that this kind of two phases microstructures contain a fine grained ferri-tic matrix and fibrous martensite, theretore, improve the level of stregth and ductility.
Abstract: The stress-strain behaviour of 55SiMnVB steel after quenching and tempering has been investigated. The results show that 55SiMnVB steel demonstrates softening in the tempering temperature range of 280-520℃, and the degree of softening is dependent upon tempering temperatures. When the steel is tempered above 400℃, dynamic yield strength linearly decreased with increasing tempering temperatures.
Abstract: The influences of six kinds of conditioning heat treatments and different effective titanium contents on the behavior of austenite grain coarsening were studied. Compared with 18CrMnB steel, the mechanism of combined effect of titanium and vanadium on the refinement of austenite grain of 18CrMnVB steels was analysed.
Abstract: This paper studies the measurement method of martensite carbon content of high carbon alloy steel which is quencShed in two phase fields. Through theory analysis a mathmatical relation between martensitic {112} crystal plane diffraction peak is established. In order to simplify the calculation process and make the method more useful in practice, a calculation program is designed. Through measuring some steels whose carbon contents of martinsite are known, the reliability of the method is proved. In the stady of 86Cr3 steel, the curves of relation between quench temperature and holding time with the carbon contents of marfensite are gained by useing this method.
Abstract: TEM morphology and mechanical properties of two Mg-PSZ ceramics were investigated. The samples of 7.98 mol % MgO was two phases, cubic and tetragonal, at the sinter temperature. The tetragonal phase was coarse and transformed totally into monoclinic one with martensitic mechanism during cooling. Inside the monoclinic particles, there were twins developing from boundary to boundary, where appeared wide microcracks with little toughening effect.
Abstract: By using TEM and tensile test, the feature of recovery kinetics in cold- drawn as-hot-rolled Si-Mn dual-phase steel was investigated. The results show that when the steel was heated for 30 min at≤500℃, only recovery process was occurred. Heated at 500℃, the activation energies of recovery process of the steels are 187.9kJ/mol(steel J) and 220.6kJ/mol(steel H) respectively. These values are close to the self-diffusional activation energy of iron in α-Fe(239.7kJ/mol). It is considered that the recovery process at this temperature is controlled by the self-diffusion of iron in α-Fe.
Abstract: The influence of silicon on the proceedings of the recovery and recrystallization of the cold-drawn Si-Mn dual-phase steels was researched by means of SEM, TEM and HV-hardness. Experimental results show. (1) The proceedings of the recovery and recrystallization of experimental steels appeal firstly in the original ferrite phase of the dual-phase structure, and it is discovered that the formation of a recrystallized grain through the growth of subgrain boundary or subgrain coalescence, and in the ferrite field the recrystallized α-grain size is larger than the recrystallized α-grain size in the marlensi te field. (2) The proceedings of the recovery and recrystallization were delayed obviously increasing silicon content of steel. (3) The recovery activation energy and recrystallization activation energy were calculated respectively.
Abstract: Hydrogen-induced cracking could initiate but Only propogate a small amount in a precharged WOL specimen of Ti-24Al-11Nb alloy at room temperature. The KIH and da/dt of hydrogen-induced cracking in hydrogen gas at 400℃, however, could be measured. Hydrogen-induced cracking on the surface initiated discontinuously within the plastic zone when the plastic deformation developed to a particular and reproducible extent, which was similar to that of the Cleavage crack in an uncharged specimen with increasing KI. The fracture surface of hydrogen-induced cracking in hydrogen gas at 400℃ was in close relationship with microstructure and basely identical with that of overload failure at room temperature but was more brittle than that of overload failure at 400℃ for all microstructures
Abstract: A simple fcc Cr carbide was formed for the firal time by carbon ion implantation into Cr thin filma. Lattice constant determined by electron diffraction was 0.403nm. In situ annealing in TEM showed it exited upto a temperature about 250℃. The carbide phase was further confirmed by Auerg electron spectra. The meidema heat of formation was - 29.4kJ/mbl.
Abstract: It was proved by S. Win in 1982 that if the sum of the degree of nonadjacent vertices of a simple graph G of order 2n is at least 2n + 1, then G has a Hamilton cycle and a 1-factor which are edge-disjoint. In this paper, it is proved that, under almost the same condition as Win's theorem, G has at least two Hamilton cycles and a 1-factor which are edge-disjoint.
Abstract: This article gives a method by which the thermal faiigue resistance of engineering materials can be measured through spherial specimen. The pare-meters of upper temperature T, cylc time n and fracture depth d are recommended as the quantitative indexes of measuring the thermal fatigue resistance of engineering materials. Three kinds, thirteen specimens were tested using this method and the test result have proved the feasibility of the method.
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
