Advanced Materials Research Vols. 146-147

Abstract: The argon-hydrogen co-injection tests were carried out in a multifunction ladle furnace (LF) equipped with a hollow graphite electrode. About 80 kg low carbon steel were refined in LF, the argon-hydrogen gas mixtures were injected onto the melt through the hollow graphite electrode, the flow rates of the gas mixtures were 3 m3/h. Then, applying the plasma local equilibrium thermodynamics and metallurgical thermodynamics theories, a calculation model of argon-hydrogen plasma component concentration was established. Using this model, the particle densities of the argon-hydrogen system were calculated. The decarburization mechanisms during Ar-H2 injection in LF with hollow graphite electrode were studied. The results show that, in the process of traditional LF refining, the carburetion reaction occurs with using the graphite electrode. When the argon-hydrogen was injected into LF, there was a decarburization reaction on the interface of the melt. Compared with the traditional LF, the carburetion rate reduces 33.3% at least. The partial pressure of C2H2 produced by molecule hydrogen is far lower than that of CH4 reacted by monatomic hydrogen. The possible main reactant gas is monatomic hydrogen and the main product is CH4.

Abstract: In order to investigate the effects of Ti, Zr deoxidants on inclusions and microstructure of low carbon steel, the experiments by Ti and Zr addition were carried out. After smelting, forging, and rolling of the steel, the effects of Ti and Zr deoxidation on inclusions and steel microstructure were studied. The inclusion characteristics (size, quantity, morphology and composition) of samples were analyzed using optical microscope and scanning electron microscopy (SEM), and the grain size and density were measured. The following results were found. The diameter of most inclusions is less than 3 μm. A linear relationship exists between inclusions density and Ti content when Ti content ranges from 0.004% to 0.032%. With the increasing of the Ti content in steel, the proportion of inclusions diameter less than 0.5 μm decreases. The inclusions distribution changes a little when Ti content ranges from 0.01% to 0.03%. The typical inclusions are TiN and TiN-MxOy, with oxide core and MnS wrapper layer, and the components change with Ti content. The average grain equivalent diameter ranges from 11.8 to 15.9 μm in the experiments. The consistent linear relationship exists between grain density and the total density of the inclusions with the diameter range from 0.5 to 3 μm.

Abstract: The effects of deoxidization and wire feeding operation on the type of titanium, magnesium and aluminum spinel compound inclusion were investigated in 409L stainless steel production process. Further, the formation mechanism of the compound inclusion was also researched at the same time. The results show that the spherical compound inclusion formed in molten steel presents clearly hierarchy after Ti injection in VOD refining process, where the inclusion size is about 5μm to 10μm. The MgO-Al2O3-TiO2 phase of compound inclusion presents regular configuration. MgO and Al2O3 content in compound inclusion decreases gradually together with CaO and TiO2 content increasing from interior to exterior of inclusion. The biphase structure of MgO·Al2O3-TiO2 will be formed with TiO2 dissolving into MgO·Al2O3. On the condition that Ti content is controlled at 0.25 wt.% together with w(Al)<0.01 wt.%, TiO2 solubility is generally less than 20 wt.% in MgO·Al2O3-yTiO2, as y< 0.44.

Abstract: In this paper, a new capillary model and weight-classification method are proposed and a device is designed and fabricated, which is helpful to measure the μm-scaled pore size of fabric and hence accurately control wet processing and heat-moisture transportation in fabric. The histograms and curves show that the pore size distribution for the cotton fabric used is generally in the range of 49-2391μm exhibitng a continuous character, different from the conventional geometric jumping distribution observed by microscope. Using four classes with different width, the obtained data show that the absolute deviation region is in 2-32μm, while the relative deviation is less than 0.1%. It is found that the radius range reduces but the absolute and relative deviation fluctuate with increasing the width.

Abstract: Poly ether-carbonate diols were synthesized by ring-opening oligomerization of ethylene carbonate (EC) initiated/catalyzed by propylene glycol/[bmim]Cl-(SnCl2) system. It was shown that the oligomerization was accompanied with decarboxylation and chain cleavage. The stronger the lewis acidity of ionic liquid, the better the catalytic performances. The biogradability of the polyurethane foams which was prepared by poly ether-carbonate diols (or common polyether polyos ZS-4110) and diphenylmethane diisocyanate (MDI) was determined by soil burial and found to be influenced by the content of carbonate unit, molecular weights and the hydroxyl value of polyols respectively. Poly ether-carbonate diols can reduce the amount of MDI in synthesis of polyurethane foams.

Abstract: To investigate the contribution of yarn pore size distribution to fabric pores structure, in this paper, based on the balance relationship between the capillary height and the hydrostatic pressure of the liquid in the yarn, we designed and assembled a device for measurement of μm scale pore size distribution of the cotton yarn. Through comparison and analysis of data and considering the very low water content in the yarn, we increased the number of yarn, designed a special cutting device and improved the measurement accuracy of weight. Finaly, we obtained histograms and curves with highly accurate (0.0001g) and good reproducibility. The results show that the yarn pore size is in tens-hundreds μm and displays a concave-like distribution, while the fabric pore size change is much more complex, suggesting that the pore in the fabric is not a simple summation of the pore in the yarn.

Abstract: The diffusion coefficient in the metallic glass-forming systems such as Pd-Cu-Ni-P exhibits a marked deviation from the Stokes-Einstein (SE) relation in the proximity of the glass transition temperature. Such a deviation is characterized by the fractional exponent p of the modified SE expression. For the material Pd43Cu27Ni10P20, it has been reported that it takes the value p = 0.75. In this work, it is shown that the value of p is highly correlated with the ratio ED / ENB, where ED and ENB are the activation energies for diffusion coefficient D and cooperativity NB defined by the Bond Strength-Coordination Number Fluctuation (BSCNF) model. The present paper reports that for the metallic glass-forming melt Pd43Cu27Ni10P20, the fractional exponent p can be calculated accurately within the framework of the BSCNF model.

Abstract: Metal content of metallized fiber can be determined by density testing and calculating. The weight of plated metal’s percentage of metallized fiber can be derived form measuring the weight of metallized fiber, and using the density formula and the law of conservation of mass with knowing the density of plated metal and the basic fiber. The characterization and measurement of the metal content of the metallized fiber at home and abroad is compared, the principle of the determination method by density testing is analyzed, the principle of the determination method by density testing is analyzed, and the specific operation is discussed while the silver content determination of silver-plated fiber is as an example, which provides a simple and convenient means for the determination of metal content of the metallized fiber..

Abstract: Due to the energy balance control of aluminum reduction cell has not solved so far, it analyzes the impact factors on electrolyzer’s heat balance (i.e., electrolyte temperature), and proposes a corresponding method of heat balance control ,which provides relevant measures for aluminium electrolysis industry ,s energy saving.

Abstract: The influence of Zr on the property of Cu(50+x)Zr(40-x)Ti10 (0≤x≤30 at.%) alloys were investigated. The results show that the maximum size for the glass formation in this Cu-Zr-Ti system is less than 8 mm. The hardness increases with decreasing of the Zr content, then decreases when the Zr content exceeds 10~15 at.% due to the obvious alteration of the type of the crystalline phases and the microstructure. With decreasing of the Zr content, the transformation sequence of the main Cu-Zr phase is Cu10Zr7→Cu5Zr→Cu51Zr14; the transformation sequence of Cu-Ti phase is Cu4Ti3→CuTi→CuTi3. In addition, the atom ratio of Cu60Zr30Ti10 alloys is coherent with that of their corresponding crystalline phase, resulting in its better glass forming ability.