Abstract: The monolithic support method is introduced based on studying properties of soft rock and influence of drivage on stress and displacement fields around opening.The monolithic support condition and a method of determinating national parameters for bolting,shotcreting and wire mesh are given.
Abstract: The microstructure and porosity of high speed steel (HSS) prepared by spary forming have been studied with optical microscope and scanning electron microscope (SEM). Compared to the casted high speed steel with the same composition, the results show that microstructure and the main mechanical properties of the high speed steel prepared by spray forming are superior.
Abstract: The influences of Ce and P on embrittlement transition temperature in Mn steel has been investigated by impact test, SEM, TEM and Auger spectrometer. The results indicate that the segregation of phosphorus along the austenitic grain boundary increases the embrittlement transition temperture, and Cerium adding to steel can minimize the degree of segregation and improve the impact toughness, therefore the embrittlement transition temperature is decreased.
Abstract: Based upon the research for the model about the prediction method of pitting fatigue life for gear, this paper applies stochastic time series to handle the changing factore with time in the model, and solves the difficulty and establishes the method system in the prediction of pitting fatigue life for gear in theory.
Abstract: The paper discusses the use of Weibull distribution of three-parameter to describe the fatigue life of machine element, and proposes a new method to fitting R-S-N curves under certain confidence. The parameters of three-parameter Weibull distribution are estimated by optimization, based on the samples of stress-life from tests. The fatigue life at each different reliability is then calculated under centain confidance. Thereafter the C-R-S-N curves can be fitted and the corresponding fatigue limit stress is evaluated
Abstract: The key point is put at planning system of the direct hot charge rolling (DHCR)in iron and steel production which is the higher production mode connecting steel making,continous casting and hot rolling. This paper discusses the way to realize the planning system and puts out a relatively detailed draft.
Abstract: Under theoritical study and analysis signal of gear vibration by various processing methods, some effective criteria are summed up and the expert system is set up. In this system, in order to make uncertain reasoning, fuzzy theory is applied to knowledge presentation;the backward reasoning mechanism controlled by meta-knowledge is adopted; the reasenable explanation according to the reasoning result is attached as well, The other features of this system are:1) not only being useful for automitic diagnosis by itself but used for pricise diagnosis cooperated with other methods, and 2) having consideration of both on-line monitoring and off-line analysis at the same time.
Abstract: The problems of Heat-Heat Mixing Charge (mixing CC-DHCR with CC-HCR) and Cold-Heat Mixing Charge (mixing CC-DHCR with CC-CCR) are researched. On the basis of characteric value models of inventory buffering, mathematical models of production logistics are posed according to situation of Mixing Charge.
Abstract: This paper describes the optimized soaking process and its cutting action of the wheels soaked in KI solution. By employing the soaked wheel, the pores cloging and chip sticking on the surface of the wheel are greatly improved, which results in the lower cutting force and temperature and improved surface quality. Besides the simple soaking process, it is also convenient and inexpensive.
Abstract: This paper investigated the antiwear properties of composite coatings with Ni-P as matrix and SiC or WC as the dispersing agent, containing mixed rare earth in the solution.The results show that the coatings of Ni-P-SiC and Ni-P-WC possess antiwear capacities in low-stress abrasive wear, and their service lives are respectively 5 and 4.5 times longer than that of the uncoat plain carbon steel Q235. The effect of particle concentration and electroplating time on antiwear capacity is also studied.
Abstract: This paper discribes a variable speed system of the bnushlss dc motor controlled by 8098 single chip microprocessor. An approach to position sensorless is studied and velocity regulator is realized by a kind of FUZZY controller. Experimental results show that the brushless dc motor can operate successfully without position sensor, and the FUZZY controller of the brushless dc motor has desirable controlling effect.
Abstract: A new technique of measuring voltage in VVVF frequency converting speed control is presented. Basing on single chip microcomputer MCS-8098, the technique uses synchronous sampling in hardware and quasisynchrouous sampling in programming. Some other techniques speeding up the running velocity of programming are also suggested. By DFT, an accuate result can be obtained for each harmonics.
Abstract: Taking account of complecities of the Functionally Gradient Materials (FGM) fabrication process, a neural network based expert system which estimates the properities of the material is presented. The experimental results show that this method is effective. To improve the learning speed of the system and reduce the possibility of local minimum, a functional-linked net is introduced. The application indicates that both learning speed and accuracy of the estimation are satisfactory.
Abstract: In this paper, the performance and principle of the synchronous PSD have been analysed. Using the digital phase shifter controlled by the 8098 microcomputer, the synchronous heterodyne PSD system has been researched and test have been carried out.
Abstract: This paper introduces the construction of two-level computer measurement and control system of rock crystal growing in the high pressure reactor. It focuses on the method of task installation and the factor which should be considered about the lower-computer in the running environment of Real Time Multi Task OS-iDCX51. The paper also offers the control tactics used. The system's control precision is about one centigrade,and it meets well the technological inquirements on the spot.
Abstract: Mischmetal ML (La-rich) was used to study MLNi3.85-xMn0.4Co0.75Alx(x=0.1~0.5) hydrogen storage alloys. Their activation processes and hydrogen absorption-desorption performances were investigated. The results show that the increase of aluminum content in the alloy can lower the plateau pressure and decrease the amount of hydrogen absorbed. It seems that MLNi3.85-xMn0.4Co0.75Alx(x=0.1~0.3) alloys are prospective.
Abstract: Using the solid electrolyte oxygen sensor with (Mo/MoO2) reference electrode to quickly measure the activity of oxygen in molten Co-based alloys, the good results were obtained. The relation was obtained between the standard Gibbs free energy of solution of oxygen in liquid Co which is necessary for calculating the activity of oxygen and temperature by using the solubility of oxygen in the liquid Co being equipoised with CoO.
Abstract: The effects of composition and deposition parameters on Ni content in deposit and appearance of specimen were studied. The additives were chosen, and bright, fine crystalline Zn-Ni alloy deposits were obtained, whose corrosion resistances are 6 times as much as Zn deposits. The properties of bath and deposits were also studied.
Abstract: The effect of RE on atmospheric corrosion resistance of carbon steel(A3),08CuPV and 09CuPTi steel has been investigated by outdoor exposure test,electrochemical alternate immersion test and alternative impedance method. The experimental results show that RE can increase resistance to atmospheric corrosion for 08CuPV and CuPTi, but no influence on carbon steel.
Abstract: Based on the steric effect,ligand packing around the uranyl equatorial plane should be neither overcowded nor undercrowded. The sum of Ligand's Fan Angle(FAS)around the uranyl equatorial plane provides a useful criterion for estimating steric crowding.FAS of UO2(OAc)Br(TBP)2 is 180°indecating the most favorable packing. It is therefore expected that a higher extraction efficiency should coincide with the formation of the more stable complex. The above speculation was confirmed by extraction of uranyl ion in the substrates of sodium acetate-acetic acid and sodium bromide. Keeping the total concentration of substractes constant, synergistic extraction is found at l:10 acetate to bromide ratio. The extracted complex was proved to be UO2(OAc)Br(TBP)2 by using the slope method.
Abstract: Taking manpower resource management problems of the Ministry of Metallurgical Industry as background, the concrete design method of Manpower Resource Intelligent Management System (MRIMS) is given. In this system, general management analysing and forecasting model tree is used as its knowledge representation. Its system structure is supported by multi-base structure. In its inference engine, meta-knowledge inference is applied to coordinate with quantitative inference, qualitative inference and neural network inference. Finite natural language understanding is introduced into the man-machine interface of the system. TURBO PROLOG and C languages are used to implement the design partly on IBM/AT microcomputer.
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
