Papers by Author: Bi Jia

Abstract: Industrial solid residues and poor quality clay as main raw material were used to prepare porous ceramic balls by ceramics process with coal and wood powder as pore-forming additive to improve the porosity of the ceramics ball. Effect of pore-forming additive on the properties of ceramic ball was investigated. The phase composition and section morphology of the ceramics balls was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The apparent porosity and crushing force of the ceramic balls were tested by Archimedes hydrostatic weighing method and crushing strength tester respectively. The tested results showed that the apparent porosity of the porous ceramic balls mainly influenced by species and addition amount of the pore-forming additive. The apparent porosity increases with the adding of the pore-forming additive. The apparent porosity and crushing force of the optimized porous ceramic balls was 49.68% and 1.17 kN respectively, which is a potential candidate used for waste water filtration.

Abstract: The microwave properties of Glass-coated FeCuNbVSiB and CoFeNiSiB microwires/dielectric composite with different microwires diameters were studied. Relative complex permeability and complex permittivity was measured by transmission/reflection (T/R) coaxial line method at the frequency range of 2-18 GHz for composite samples. The results show that the microwave permeability and permittivity increases with the lengthening of the microwires in composite. The microwave permeability, natural resonance frequency and microwave permittivity increase with the decrease of the diameter of the microwires.

Abstract: Some problems have seriously affected the implementation of smelting ferrochromium in the argon-oxygen furnace. This paper discussed reducing chromium loss and controlling excessively high bath temperature by thermodynamic analysis. The results show that the process is divided into two stages and the critical carbon concentration of its switchover point is controlled in the range of 1.5%-2% to reduce chromium loss; dynamic control of oxygen and argon supply by theoretical calculation and AI(Artificial Intelligence) technology and carbon dioxide blown by a lance with double channel as coolant instead of steel scrap and chrome ore can flexibly control furnace temperature.

Abstract: The porous ceramic filter balls were synthesized with industrial solid waste by ceramic process. The removal efficiency, filtration velocity and turbidity for the water treatment properties of the porous ceramic ball filter materials was studied comparing with that of the quartz sand filter materials. The test result shown that the decontamination efficiency of the porous ceramic ball filter was 5% to 10% high than that of the quartz sand filter. When the water turbidity fluctuated with magnitude about 50%, the changes of final water turbidity was in the range of 5% to 8% through the porous ceramic ball filter. The energy saving efficiency of the porous ceramic ball filter was very significant for the porous ceramic ball filter effectively extend the filtration cycle life.

Abstract: The magnetic structure of the glass-coated magnetic alloy microwires were modeled based on the main magnetic domain structure and meshed by finite element method. The magnetic spectrum of the magnetic alloy microwires was calculated based on the micromagnetic theory. The simulation results of the magnetic spectrum of glass-coated magnetic alloy microwires showed that the magnetic anisotropy field increase as the magneto-crystalline anisotropy constants increase. The microwave resonance frequency increased accompanied by the reduction of the permeability and the increase of the magnetic anisotropy field of the glass-coated magnetic alloy microwires.

Abstract: Glass-coated FeCuNbVSiB microwires was annealed in the temperature range of 380 °C to 600 °C. The microstructures and magnetostatic properties of the glass-coated microwires were characterized by X–ray diffraction (XRD), Vibrating Sample Magnetometer (VSM) respectively. Relative complex permeability and complex permittivity was measured by transmission/reflection (T/R) coaxial line method in the frequency range of 2-18 GHz for as-casted and annealed Fe-rich microwires samples. The measured results show that the coercive field of the Fe-rich microwires decrease to 1.54 Oe at 470 °C, and then increase rapidly with the increasing of the annealing temperature. The coercive field and saturation field of the microwire samples increased abruptly with the outgrowth of the Fe-B hard magnetic phase in the Fe-rich microwire samples. The imaginary part of permeability and the natural ferromagnetic resonance frequency decrease for the thermal treatment below 470 °C, and then increase with the annealing temperature up to 530 °C. The change of magnetostatic and microwave electromagnetic properties of the microwires samples with the annealing process come from the change of the anisotropy caused by the internal stress.

Abstract: The atmospheric corrosion has been shown to be an electrochemical process, the atmospheric corrosion behavior of Q235 stell evaluated with ACM (Atmospheric corrosion monitor) electrochemical technique was investigated in the study. The experimental results showed that there existed a close relation between electrochemical data and climatic parameters was confirmed. Taking into consideration accuracy and sensitivity of electrochemical technique, the ISO-standardized time of wetness (TOW) seems to be too conservative. SO2 seems to be more aggressive than chloride on metal corrosion in the early stage of atmospheric corrosion but the complexion reverses in the final stage of atmospheric corrosion. The ratio of corrosion rate from integration of ACM current to corrosion rate from weight loss of test specimens, that is, cell factor is fairly constant at the same test site but varied greatly between test sites. Based on constant cell factors and close relation between electrochemical data and climatic parameters in all test sites, ACM electrochemical technique can evaluate and classify the short-term atmospheric corrosivity as a substitute for gravimetric method, and the verification shows that atmospheric corrosivity classifications according to integration of ACM current and especially to cell factor coincide with the specifications of ISO Standard.