Advanced Materials Research Vol. 813

Abstract: To acquire the digital model of axial compressors on the actual projects, a Reverse Engineering procedure of the blade which has high accuracy and efficiency based on Parametric Modeling was developed. To meet the requirements of geometric characteristics and aerodynamic optimization design and accuracy of overall blade, a method of blade-measuring path planning based on curves of cross sections and blade body surfaces was presented. For solving the problems of difficulty in the definition and fitting in primary parametric surfaces and connections between them, a parametric surface definition method of typical axial compressors blade based on blade geometry was presented and the connections were fit with a process of primary parametric surface boundary-splicing surface generation. Finally, an example of Reverse Engineering for blades of axial flow compressors based on parameterization was given.

Abstract: As a pre-treatment process for producing solar-grade silicon, hydrometallurgical method could remove the most of metallic impurities of metallurgical-grade silicon, which is a hopeful technology to provide solar energy material independence of the Siemens skill. Factors such as the hydrochloric mass fraction, temperature, reaction time, and particle size of silicon powders were investigated in the impurities removal experiments under the condition of mechanical stirring. The leached samples were analyzed by ICP and SEM. The optimum parameters, hydrochloric mass fraction 5%, temperature 80°C, reaction time 9h, particle size 75μm, were determined by single factor experiments and orthogonal experiments. The 86.1% of Fe, 68.1% of Al, 85.9% of Ca and 25.9% of B impurity was removed from metallurgical-grade silicon powder.

Abstract: This paper presents a detailed analysis of impurities distribution in metallurgical-grade silicon after CaO-SiO2-CaF2 and CaO-SiO2-CaCl2 slags refining. It demonstrates that the impurities removal efficiency generally increase in metallurgical-grade silicon after CaO-SiO2-CaCl2 slag refining compared to that after CaO-SiO2-CaF2 slag refining. It is also determined that metallic impurities like Fe, Al and Ca tend to co-deposit with Si to form Si-Ca based intermetallic compounds in the precipitate phase after slag refining.

Abstract: This work used Artificial Neural Network (ANN) to investigate the hysteresis behavior of the Ising spins in structures ranging from one-to two-and three-dimensions. The equation of magnetization motion under the mean-field picture was solved using the Runge-Kutta method to extract the Ising hysteresis loops with varying the temperature, the external magnetic field parameters and the system structure (via the variation of number of nearest neighboring spins). The ANN was then used to establish relationship among parameters via Back Propagation technique in ANN training. With the trained networks, the ANN was used to predict hysteresis data, with an emphasis on the dynamic critical point, and compared with the actual target data. The predicted and the target data were found to agree well which indicates that the ANN functions well in modeling hysteresis behavior and its critical phase diagram across systems with different structures.

Abstract: In order to identify the mechanisms of changes in the magnetic flux density distribution around fatigue cracks that occur during crack propagation, JIS SCM440 specimens were fatigue tested, and the relation between crack morphology and magnetic flux density distribution was investigated. Two features were observed: a high intensity area around the crack tip, and a low intensity area around the crack root. The low intensity area grew larger for wide open cracks and disappeared when the crack was closed by external force. It was hence found that the magnetic flux density distribution is strongly affected by the crack opening.

Abstract: For the jack-up platforms' huge size and complex structure, as well as the variation and complexity of their ambient corrosion environment, problems often arise in cathodic protection (CP) systems. The rise of the computer and the numerical simulation technology provide a new technical method to the prediction, evaluation and optimization of CP system for jack-up platform. Numerical simulation method has the advantage of examining potential maps of the entire structure easily and then the designer can determine the number and placement of anodes required to provide protection from the under and over protection regions based on a generic polarization response. In this paper the 3-D boundary element method was used to calculate the mathematical model of sacrificial anode CP system for a jack-up platform. Introduced piecewise quasi linearized method to deal with nonlinear problem of boundary conditions. Adopt block boundary element method to solve electrolyte inconsistency problem and points regional modeling to solve electrolyte discontinuous. From the results we can conclude that the jack-up platform sacrificial anode CP system meets the protection targets.

Abstract: This paper aims at getting a way to obtain the suitable track tension by analyzing a heavy tracked vehicles driving prototype which is consisted of the sprocket and the meshing tracks. First, by analyzing the force state in the driving part in the multi-body dynamics simulation tool: RecurDyn, a critical condition to judge the peel-off of tracks in heavy tracked vehicle is proposed. Second, by comparing the different models built in RecurDyn, an ideal track distribution around the sprocket is obtained and also the relationship between the driving torque and the track tension under that ideal situation is concluded. Third, basing on the data from the simulation, the force state of each track meshed with the sprocket is analyzed, and an assumption about the proportion between each tracks upper and bottom pulling force is proposed.

Abstract: The microstructures and bending properties of STS439/Al1050/STS304 clad plates were investigated after annealing process at various temperatures. Interfacial layer was developed at the STS439/Al1050 and Al1050/ STS304 interfaces at 550^OC. The presence of Al3Fe2 at the STS/Al interface was confirmed by EDX. The initial bending hardenability and load under condition A (STS439 side in tension) was found to be greater than under condition B (STS304 side in tension). The higher hardenability and load under condition A can be explained by the greater strain hardenability of STS439 (bottom side) in tension. No interfatial cracks were observed across the interface in the as roll-bonded clad composite and annealed clad composites at 450^OC. After annealing at 550^OC, the load drops in the early part of load-displacement curves associated with the interface debonding was observed. As-rolled clad metal and that annealed at 450^OC exhibited the relative high load.

Abstract: In order to investigate corrosion and soldering behaviour of STD61, TiN and TiAlN were coated on the surface of STD61 by using Arc Ion Plating. The structure of the coatings was examined as a function of deposition conditions by X-ray diffraction, and the crystallographic orientation was determined by use of a texture coefficient. TiN coating was grown with a strong (111) preferred orientation of a typical NaCl-type crystal structure. This strong (111) preferred orientation had been commonly observed from the TiN coatings deposited by physical vapour deposition techniques. TiAlN coatings, however, showed relatively multiple orientations mainly of (111) and (200). Furthermore, TiAlN film demonstrated superior corrosion resistance in a molten aluminum alloy at 680°C. This paper described in detail the corrosion and mass loss phenomena related to this steel-cast metal interaction.