Advanced Materials Research Vols. 148-149

Abstract: The updating geometric method was proposed to simulate the deformation behavior of workpiece during multipass shape rolling by using finite element method. Firstly, establish and solve the finite element model of the first pass shape rolling process, then update the geometric shape of workpiece after the first pass and delete rolls of the first pass, establish and mesh rolls of the second pass, modify the boundaries and material parameters of workpiece, and solve its deformation behavior during the second pass shape rolling. With the same steps, its deformation behavior during the following passes rolling could be solved. The method was applied to simulate the deformation behavior of a cube workpiece during six-pass H-beam rolling with split-rolling, and its shapes after every pass rolling process were obtained. Experiments on the deformation behavior of slab during multipass rolling were carried out by using pure lead in an experimental mill. The calculated results are in good agreement with the experimental ones.

Abstract: Experiments were carried out to investigate effects of extruding parameters on soybean oil yield extracted with enzyme-assisted aqueous extraction. It was found that extrusion and expansion parameters affected significantly on total soy oil yield. Optimal extrusion and expansion parameters for highest total soy oil yield were obtained using response surface methodology. Effect of extrusion and expansion pretreatment on soy cells was studied using light microscope and transmissive microscope. State of free oil and protein during hydrolysis was observed using light microscope. Ultrasonic assistant ethanol de-emulsification was found the effective method to destabilize the emulsion.

Abstract: Slurry preparation is of paramount importance in chemical mechanical planarization (CMP) process. It couples the combination effects of chemical and mechanical ones. In this paper, the characteristics of the slurry particles used in CMP are firstly modeled, which includes the size and the concentration with primary priority. And then, the model is validated by experiments during hard disk wafer polishing. The slurry prepared contributes to a high quality hard disk surface processed with CMP, which leads to low waviness Wa and roughness Ra with suitable material removal rate (MRR) as well. The study will surely lay a feasible foundation to the CMP mechanism.

Abstract: The disadvantages of discovery mechanism of current network manufacturing resource were analyzed. A joint discovery mechanism based on UDDI (Universal Description, Discovery and Integration) and WSIL (Web Services Inspection Language) was put forward. Two-level matching was put forward. Basic process features are matched in UDDI and corresponding feature values are matched in local WSIL .Network manufacturing resource discovery architecture was built. Basic principles and characteristics of the integrated architecture were analyzed. Key technologies for realizing the integrated architecture were studied. The joint discovery mechanism prototype platform for manufacturing resource was developed by borrowing ideas from this model. The framework improves retrieval efficiency, greatly reduces the load on UDDI.

Abstract: It is very important for reservoir management to estimate the sedimentation amount deposited in a reservoir. Firstly, the formula for estimating the bed load transport rate in the bed of sand waves of prototype by model experiment was derived based on the similarity of grain Froude number; Secondly, several model experiments that the bed forms is similar with the prototype were carried, and the formula was verified. As a result, when the ratio of grain diameter in the prototype and model is great enough, and the bed forms in the model is similar with that in the prototype, a satisfactory result can be obtained by using the estimation formula for estimating the bed load transport rate of the prototype that sand waves occur in the bed.

Abstract: The model of ultrasonic propagation at a solid-solid contact interface was established. Higher-order harmonic wave generation and waveform distortion take place when the ultrasonic wave propagation at the solid-solid contact interface. Aluminum wire bond experiments were performed on a laboratory test bench. The relation of bond strength, nonlinear coefficient and contact interface pressure was studied. The experiment results show that when contact interface pressure is less than 6 kPa, higher-order harmonic wave component and the nonlinear coefficient decrease and bond strength increases with contact interface pressure increasing, when contact interface pressure is in range of 6 kPa to 10 kPa, higher harmonic wave and the nonlinear coefficient is the least and bond strength is the highest, however, when contact interface pressure is more than 10 kPa, the nonlinear coefficient increases and bond strength decreases with pressure increasing. The nonlinear coefficient of ultrasonic is a method of forecast bond strength.

Abstract: In this study, an integrated methodology combining computational modal analysis, experimental modal analysis, and computational dynamic analysis was developed to investigate unbalancing dynamic responses of high speed machining tool systems. A linear-elasticity formulation based on the finite element method (FEM) was employed to compute the natural frequencies and obtain the corresponding modal shapes. Experimental modal analysis was then performed to verify the natural frequencies. After the validation, the FEM model was further modified to predict the dynamic responses, with an HSK (a Germany abbreviation of Hohl Schaft Kegel) tool system as a model system. The results indicated that, by validating the computed natural frequencies with experimental ones, an effective simulation model can be established for predicting complex dynamic response of high speed machining tool systems.

Abstract: For the disadvantage of traditional production mode, an operation optimization model is put forward on the basis of analyzing workshop production system operation. The Features of the model are real-time, dynamic, multi-objective and multistage. The algorithm called ‘Harmonizing Cluster Results’ for the model is presented in order to solve the difficulties of solution for the workshop production system operation model. Then the model is simplified into some submodels, such as production ability optimization submodel, time optimization submodel, balancing and harmonizing submodel etc. Finally the operation optimization model and its solution algorithm are applied to an assembly line of energy meter in a factory. With the help of ‘Witness’ the application case simulation results showed that the model is accurate and its solution algorithm is reasonable and available.

Abstract: A mathematical model was established to describe the electromagnetic, heat flow and fluid flow phenomena within a combined plasma arc. In the development of the model allowance is made for the conservation of mass, momentum, energy and the Maxwell equations. With the ANSYS finite analysis software, specific calculations were presented for a pure argon system, operating in a laminar mode. The distributions of the current density, temperature and velocity of combined plasma arc were gotten. In addition, the influences of process parameters, including arc current, argon gas flow rate and the distance from the nozzle outlet to the anode workpiece, on the temperature distributions along the axial and radial direction were evaluated, respectively. The results shows that the temperature of combined plasma arc is much dependent on the working current, while is less sensitive to the argon flow rate and the distance from the nozzle outlet to the workpiece anode.