Advanced Materials Research Vols. 641-642

Abstract: Abstract. Effect of oxidation on phase transformation in Ti-bearing blast furnace slag is studied. The slag is analyzed by X-ray diffraction (XRD) and scanning electron microscope (SEM), EDX and metallographic microscope. The experiment results indelicate that the phase composition of the oxidized slag is simpler which are only rutile and glass phase. The titanaugite, Ti-rich diopside and perovskite phase are vanished and most of the Ti components were enriched in the rutile phase.

Abstract: Abstract In the present study, an attempt has been made to investigate the effect of cutting parameters (cutting speed, feed rate and depth of cut) on cutting forces (feed force, thrust force and cutting force) and surface roughness in milling of Quartz glas using diamond wheel. The cutting process in the up-cut milling of glass is discussed and the cutting force measured. The cutting force gradually increases with the cutter rotation at the beginning of the cut, and oscillates about a constant mean value after a certain undeformed chip thickness. The results show that cutting forces and surface roughness do not vary much with experimental cutting speed in the range of 55–93 m/min. The suggested models of cutting forces and surface roughness and adequately map within the limits of the cutting parameters considered.

Abstract: When the Electrorheological elastomer (ERE) is embedded into intelligence structure system, the structure damping and stiffness of the system can be changed quickly and reversibly under an external electric field. Thus, the application of the Electrorheological elastomer in the active and passive hybrid control of structural vibration has already attracted people's wide attention. In this paper, three types of ER elastomer were prepared based on barium titanate, starch, then the microstructure of ER elastomer was observed and the mechanical properties were analyzed; a shear mode ERE shock absorber was designed, the vibration response performance of which was experimentally evaluated under various excitation frequency with or without the applied field. The experimental results showed that the damping and stiffness of the shock absorber could be modified with a changing external electric field, whose macro-features was that the damping coefficient increased with the increase of the electric field, and the damping effect in the high frequency was better than in the low frequency.

Abstract: Iron ore and tin mineral are the mainly recovered minerals of the low-grade ore, which could be effectively separated by a strong magnetic separation-gravity concentration process, with ore iron grade of 20.3%, tin grade 0.18%. Stage grinding and stage separation was used, getting the grade of iron concentrate and the recovery rate of tin separation index, the feeder of tin was magnetic separation tailing, by shaking table re-election, obtained tin concentrate grade was 10%, production was 0.34% (compared to the original ore, tin dressing) .Tin concentration ratio reached more than 330.

Abstract: An experimental research on comprehensive recovery of iron and associated apatite from a low grade vanadiferous titanomagnetite ore with high phosphorus was carried out. The results showed that using the technological flowsheet of “low -intensity magnetic separation-flotation”, not only the magnetite can be effectively separated, but the associated apatite in the mineral resources can also be satisfactorily recovered. An iron concentrate with a TFe grade of 64.81% and iron recovery of 58.04% and a high-quality phosphorus concentrate of 33.50% P2O5 with a yield of 92.18% is obtained．

Abstract: This paper introduce a series of tests about properties of seawater and sea-sand concrete, such as impermeability, dry shrinkage, alternate wetting and drying destruction and sulfate attack. The test results show that the impermeability of seawater and sea-sand concrete and ordinary concrete is basically same, the coral sand leads to decreasing of concrete impermeability, the admixture can effectively improve the impermeability of coral sand concrete. The difference between the shrinkage rate of seawater and sea-sand concrete and the ordinary concrete is not obvious, the shrinkage rate of seawater and coral-sand concrete is larger than ordinary concrete, and the admixtures can effectively inhibit the late drying shrinkage of seawater and sea-sand concrete and seawater and coral-sand concrete. In the case of alternate wetting and drying, the pressure generated by the salt crystals would not damage seawater and sea-sand concrete. Potential sulfate attack exits in seawater and sea-sand concrete, the active admixture is able to greatly enhance its ability of resisting sulfate corrosion.

Abstract: Kyanite is a kind of andalusite minerals, with good refractory. In nature, it existed together with mica, quartz etc, so it is necessary to purify. Garnet kyanite schist in Hebei province as the raw ore was separated in this paper, on the basement of high intensity magnetic separation and gravity to demilish impurities, obtain kyanite rude concentrate, by proceed a series of flotation condition test research, through six- concentrate reelection, getting the flotation concentrate with grade of 56.16%,the productivity of 12.09%,the recovery of 36.82%. Meanwhile, the reason of the low concentrate grade was analysed, and the suggestion was given to deal with kyanite concentrate in the next step. It provided foundation date for the developing of kyanite separation.

Abstract: Based on the cross-section bending of 5 carbon fiber concrete beams, the mechanism of deflection and strain of carbon fiber concrete beam were studied considering the variation of the length of carbon fiber. The experimental results show that the deflection of destruction increased with the increase of the length of the carbon fiber. The carbon fiber can effectively improve the brittle failure of concrete beam, and the stain of concrete accorded with that steel bar at the same height. According to the existing test model, the theoretical calculating formula of CFRC was proposed.

Abstract: To further study the mechanical properties of carbon fiber reinforced concrete (CFRC) about carbon fiber length, and determine the optimum length of the fiber. In this paper, based on the test, the enhancement effect of four different length of carbon fiber reinforced concrete is studied. Compressive strength curves and load-deformation curves of the test blocks mixing the different lengths carbon fiber are obtained. In the loading process, the change curve of the ratio of transverse strain and longitudinal strain are obtained. The results showed that the compressive strength increase and after decrease with the increase of fiber length. When the length of carbon fiber is 10 mm, the improved effect is best, and it can effectively improve the brittle failure of concrete. When the length of carbon fiber is more 30 mm, the improved effect of deformation of carbon fiber reinforced concrete is not obvious.

Abstract: The conventional triaxial tests for cement-soil show stronger soften characteristics of cement-soil under low confining pressure. The soften character is weaken as confining pressure decrease. For adopting Duncan-Chang hyperbola model to obtain parameters of cement-soil, the model cannot include the stress-strain soften characteristics of cement-soil, and must be discussed. The paper studies on parameters of Duncan-Chang model using generalized Hooke law and nonlinear elastic theory. The researches show the parameters of k and n are unrelated to soften characteristics of cement-soil; the relation of Rf and σ3 is given by the soften characteristics, Rf influence the soften process directly. The calculation method could be used in E-u model, and has good practical value.