Intelligent Control System of BOF Steelmaking
0n the basis of analyzing BOF steelmaking characteristics, a prediction model and control model based on neural network were established. Taking endpoint temperature and endpoint carbon content as control target, oxygen-blown volume and added coolant were calculated, then endpoint control of convert steelmaking was realized. Simulation results show that the simulation result of endpoint temperature and carbon content are satisfying and control strategy is very effective. The application results demonstrate the efficiency of the method.
Magnetic Properties and Kinetics Parameters of Electroless Magnetic Loss CoFeB Films
Electroless CoFeB films with good soft magnetic properties were fabricated on polyester plastic substrate from sodium tartarate as a complexing agent. The plating rate of electroless CoFeB films is a function of concentration of sodium tetrahydroborate, pH of the plating bath, plating temperature and the metallic ratio. The estimated regression coefficient b0 2 b3 confidence interval, residual error r and confidence interval rint were confirmed by a computer program. The optimal composition of the plating bath was obtained and the dynamic electromagnetic parameters of films were measured in the 2 2 10 GHz range. At 2 GHz, the ε′, ε″ of the electroless CoFeB films were 304 and 76. 6, respectively, as the concentration of reducer is 1 g/L. Magnetic hysteresis loop of the deposited CoFeB films show a remanence close to the saturation magnetization and coercivity of about 55. 7–127. 4 A/m. The loops along the hard axis display low anisotropic field Hk of 2 388–3 582 A/m.
Microfilamentary conductor based on Bi(2212)
A series of ex situ prepared microfilamentary conductors has been prepared to determine the optimum heat treatment sequence for the development of a strain-tolerant microfilamentary conductor based on Bi/sub 2/Sr/sub 2/Ca/sub 1/Cu/sub 2/O/sub 8- delta /. Both monolithic tapes and the microfilamentary composites were prepared so that the difference between the two methods for the same heat treatment could be evaluated. The monolithic tapes are easy to fabricate and are used to provide a rough guide to the desired degree of melting and the optimum oxygen concentration needed for the highest critical current densities. One of the ex situ microfilamentary composites showed a critical current density of 5000 A/cm/sup 2/ at 4.2 K while subjected to a strain exceeding 1%.