Advanced Materials Research Vols. 194-196

Abstract: In this paper the impact toughness of the basalt fabric reinforced epoxy resin composites was discussed. In the test, the basalt fabricwas used to reinforce the TDE-86epoxy resin, and 70#anhydride was used as curing agent. The mode of [45°/-45°] was chosen to layering and prepare the unit-cells. Resin Transfer Molding instrument was used to cure and make the basalt fabricreinforced epoxy resin composites, and the instron-based Dynatup9250HV material impact testing machine was used to test the impact resistance. Conclusion: in the low-velocity impact test, the maximum load the sample can bear was about 9.6538kN，and the total energy the sample absorbed was 19.3030J; Observing the impact morphology of the sample, the basalt fabricreinforced epoxy resin composite was not perforated, then its failure mode was matrix cracking, drawing and fracture of the fiber. The results provided a scientific basis for basalt fabricreinforced composites, and increase the development of the production related to the basalt fabriccomposites.

Abstract: Under ultrasonic irradiation at a frequency of 20 kHz, hydraulic model experiments have been performed to improve the stirring effect in the ladle refining. The cavitation intensity and ultrasonic field distribution were measured by dyeing method. The dynamic behavior of acoustic cavitation bubbles were visualized with a high-speed digital camera. The results show that: the mixing time under ultrasonic can be reduced obviously, and the dynamic conditions can be improved apparently；stable and complete patterns can be got by dyeing method, then relative intensity and the position of antinode and node can be determined from the pattern; the distribution of ultrasonic fields at tool end is circular cone; the cavitation bubbles were confirmed to be generated around the antinode of sound pressure during the ultrasonic stiring and moved linearly in random directions.

Abstract: The effect of pre-treatment on carbide transformation and morphology of a medium-alloy high carbon steel (0.86C, 0.84Cr, 1.85W, 0.95Mo, 0.31V) with multi-elements was investigated in this paper. The results show that there are multiple types of carbides (M₃C、M₂₃C₆、M₇C₃、M₆C、MC) in the annealed steel. The morphology of carbide in the annealing microstructure largely relate to the process before annealing. Carbides with disperse spherical and short rod-like distribution exist in the ferritic matrix when the steels are annealed at 820−860°C. The spherical carbides in the ferritic matrix can be obtained by isothermal annealing at 680−720°C after heating at 800°C. The morphology of carbides with different pretreatment process relate to carbide transformation, which can be described by calculating based on phase equilibrium thermodynamic.

Abstract: In this paper, Potentiodynamic scans and Potentiostatic experiments are used to study manganese electro deposition on stainless steel and titanium substrates from simple chloride solutions with addition of ammonium chloride. The surface morphology and the crystal structure of manganese electrodeposits are analyzed by scanning electron microscope (SEM) and powder X-ray diffraction spectrometer (XRD), respectively. The comparison of electrolysis manganese craft on stainless steel and titanium, It is found that precipitation hydrogen is easier and the cell voltage is higher on stainless steel ,but there are more side reactions on titanium; The cubic crystal form manganese deposite on stainless steel and titanium, but the higher pure degree manganese can be obtained on stainless steel, the depositions on the titanium are imply impurity.

Abstract: The composite board was made of chopped basalt and polypropylene fibers. The manufacturing process included blending, carding, web formation, laminating and compression molding. The tension and bending properties were investigated experimentally. The load - displacement curve of the tensile test revealed that the elastic modulus and maximum vertical load in the longitudinal were far greater than these in the transverse direction; and tensile strengths were far apart in the longitudinal and transverse direction as well. In comparison with the tensile tests, the effect of basalt fiber orientation on the bending modulus and strength were relatively insignificant. In addition, from the micro fibril angle, we also verify that the orientation angle of basalt fiber is an important factor of influence to the mechanical property. In the similar study, the influence hadn’t been seen sufficiently, so this paper provides reference to the actual application of the composite board.

Abstract: The microstructe of mold fluxes of low-carbon steel and mould powders were researched by means of polarizing microscope. The result shows that the mineral compositions of the mould fluxes primarily are glass phase, wollastonite, quartz, melilite, pyroxene and feldspar. The main mineral compositions of mould powders is melilite. The quartz, pyroxene and glass phase are helpful to reduce the crystalline portion of mould powder, but the melilite, wollastonite help to improve the crystalline portion and promote crystallization of melilite. It is good for the crystalline portion when the casting speed droop.

Abstract: To develop 590/780MPa grade low yield ratio structural steel, the effects of ultra fast cooling (UFC) new process on microstructure and mechanical properties were investigated. The results showed that the low yield ratio and high strength can be obtained by proper phase compositions including relative soft phase and hard phase. For the process of UFC + air cooling, when UFC final cooling temperature was 521°C, 22.5% M-A second hard phases were distributed on bainite ferrite matrix in steel No.A2. The mechanical properties can meet requirement of 590MPa grade low yield ratio structural steel. For the process of air cooling + UFC, when UFC initial cooling temperature was 781°C, the multiphase composed of 28.3% ferrite and other bainite / martensite lath structure can ensure the high strength and low yield ratio of steel No.B1. And performance indexes can meet the requirement of 780MPa grade low yield ratio structural steel.

Abstract: Cementite spheroidization of GCr15 bearing steel includes granulating and growth of cementite. The effects of divorced eutectoid transformation (DET) temperatures on growth of cementite were studied. It was found that the particles of cementite are fine and uniform when DET occurs at 690～720°С, and alloy elements mostly precipitate at different temperatures during cementite growth of GCr15 bearing steel; Cr and Si mostly precipitate in the eutectoid temperature upper limit, while Mn is in the eutectoid temperature lower limit.

Abstract: In this paper, the method of cold model is applied to study raceway in COREX Melter-Gasifier drawing on the experience of raceway in blast furnace. The influence factors, blasting volume, charging rate which simulates coke consumption, bed packing height have been considered. The results show that the shape of raceway is ellipsoidal and blasting volume, charging rate, bed packing height have effect on raceway. The raceway penetration depth and raceway height expand with increasing blasting volume and charging rate. However, the size of raceway decreases with increasing bed packing height.

Abstract: The balance calculation of zinc and lead of No.1 BF of Baotou Iron and Steel Group Co. was performed in this research. The particle sizes of BF dusts were measured by LS230 laser particle size analyzer. The micrology of sinter and dusts were investigated with scanning electron microscopy (SEM, Hitachi S-3000) coupled with an energy-dispersive X-ray analysis (EDX). The results show that the general burdens of zinc and lead in No. 1 mainly came from sinter and pellet. The burdens of zinc and lead in No.1 BF were 645.45g/t and 370.33 g/t respectively, which were too much to need take some measures. Among the gas ash, the particle size of baghouse dust was minimal, but the contents of lead and zinc were highest. So the BF baghouse dust isn’t appropriate to recover as the sintering materials. The speciation of lead is PbO, PbCl₃ and metallic Pb, but zinc never presents as metal in BF dusts.