Advanced Materials Research Vol. 510

Abstract: Chemical etching, which is the most sensitive method to recover obliterated serial numbers on metal surfaces. This paper studied the method of recovering obliterated engraved vehicle identify number on aluminum engine surfaces by alkaline etching technique. Experiment research indicates that 25% sodium hydroxide solution not only can recovering original vehicle identify numbers on aluminum engine effectively, but also is easier to prepare and lower volatilizable than traditional method which uses acid solution. With the popularization of aluminum engine in motor engine, the method using sodium hydroxide solution to recovery has far-reaching application prospects, especially in the robbery cases involving vehicle identify numbers juggled.

Abstract: The Eulerian two-fluid model incorporated with the multiple reference frame approach is adopted to predict the gas-liquid two-phase flow in the novel combined top and corner spray degassing tank for aluminum melt. The influence of different parameters, such as gas velocity or hole areas at the tank corners on the gas-liquid flow behavior is also investigated. Results show that little gas emerges near the wall of tank equipped with traditional rotating spray degasser. Using the combined top and corner spray degasser, the distribution of bubbles in the tank, especially near the tank wall, is improved significantly, which advantages the hydrogen removal. With the increasing gas velocity or hole areas at the tank corners, the width of ring zone with low gas volume fraction decreases, and thus enhances the effect of hydrogen removal.

Abstract: A patching material for converter was investigated by using sintered magnesia as the main starting material, a certain carbohydrate as binder and graphite flake and Al metal as additives. The effects of the additions of binder, graphite and aluminium metal on the performances of patching materials were studied respectively. The results revealed that the carbohydrate binder melted during heating, making the patching materials spread out and flow; graphite flake could improve the flow ability, but decrease the bulk density; aluminium metal could partially be oxidized or nitrided, and hence fill the gap and increase the strength.

Abstract: In order to study the process of ionic soil stabilizer (ISS) reinforcing different kinds of soil, kaolin, red clay, landslide soil, expansive soil and quartz sand ,the five kinds of standard soil samples were treated by ISS of ratio 1:100. After 24-hour soaking and oscillation treatment, the supernatant was detected by laser-induced breakdown spectroscopy (LIBS). Comparing with the samples had not been treated by ISS, got the information of cation exchange. Experimental results showed that, the cation exchange in different soil was various, landslide soil exchanged more cation, and the cation exchange of kaolin and quartz sand was less. These studies will provide the experimental basis for ISS reinforcing mechanism research.

Abstract: Secondary ion mass spectroscopy (SIMS) has been adopted to study the diffusion of Al and Si in Cu_44.25Ag_14.75Zr₃₆Ti₅ bulk metallic glass (BMG). It has been found that around the transition temperature of metallic glass, the relation between its diffusion coefficient and the temperature satisfy the same Arrhenius relation, which means the metallic transition has not caused change to the diffusion mechanism. In addition, the radius of Al atom is close to that of Si atom, but under the same temperature and time condition, the diffusion coefficient of Si atom in bulk metallic glass (BMG) is twice that of the Al atom, while there is not a big difference in diffusion activation energy. This is because as non-metallic element, the radius of Si atom has a strong binding force with the metal atoms in the base material, which also has a bigger diffusion coefficient.

Abstract: In this paper, it was introduced that the case that under100% replacement of recycled coarse aggregate (RCA), the C30 recycled concrete was prepared by different rage fly ashes 0%, 10%, 20%, 30% replacing cement. The strength of the recycled concrete and mixtures workability were test. Eventually it is concluded that the strength and mixtures workability of recycled concrete were affected by different circumstance under the different rage and amount of fly ashes, and a theoretical basis in the impact of fly ashes in the application of recycled concrete is provided.

Abstract: This paper reports a critical summary of literature review of creep damage constitutive equations. Firstly, it introduces the general background on the creep damage in low alloy stainless steel and weldment. Then, it summarizes the typical creep damage constitutive equations for this material available from public literature and discusses the deficiencies existed in the popular creep damage constitutive equations. Finally it outlines the approach to be used in the developing a new set of creep damage constitutive equation and the directions of future work.

Abstract: When the ordinary concrete is added to fly ash, the slump of concrete is increased and the workability and pumpability are also improved, which can meet the design requirement, reduce project costs, protect environment and save resources. Based on evaluation of the basic performance for raw materials of fly ash concrete, the improved mix design method for fly ash concrete is proposed. And then it is tested in practical project to verify the workability and feasibility and meanwhile some construction attentions are proposed. The results show that the fly ash can significantly improve the workability of cement concrete. The early strength of fly ash concrete is lower than ordinary concrete, but after 28 days, the compressive strength is similar with ordinary concrete, which provides a reference for design and construction of fly ash concrete.

Abstract: The rules that optical parameters of the biological tissue simulating liquid ( Intralipid-20% diluents ) were changed along with the change of temperature were investigated by CCD imaging and photograph analyzing system, based on the diffusion approximation and extensive boundary conditions. It was found that the absorption coefficient is gradually increasing and the reduced scattering coefficient is gradually decreasing along with the increase of temperature. And by measurements of diffusing reflection light and the transmission light by CCD, the anisotropy factor of Intralipid-20% diluents was obtained experimentally. The measured value by CCD was compared with the theoretical value. The results were approximately consistent. It was shown the measuring method by CCD not only is easy operation but also has a high accuracy.

Abstract: The tool-chip friction coefficient influences the simulation result of the residual stresses distribution seriously when Finite element software is used to simulate. This paper presents a new tool-chip friction coefficient estimate approach. Frist, a new mathematical model of cutting forces, the cutting speed, feed amount and the tool-chip friction coefficient was established in this paper based on the simulation results of Advant Edge, and then the tool-chip friction coefficient was reversed when the cutting forces are measured. Comparing the simulation residual stress distribution of the friction coefficient in calculation, average coulomb friction coefficient, the default friction coefficient with experimental result; it turns out the distribution of residual stresses in the friction coefficient of calculation approaches to experimental result.