Finite Element Analysis on the Unloading Elastic Modulus of Aluminum Foams by Unit-cell Model
This paper presents finite element analyses (FEA) on the unloading elastic moduli of aluminum foams under uniaxial loading and bending conditions. The unit-cell model of Gibson and Ashby was utilized in the FEA with elasto-perfectly plastic material. Compression, tension, and bending tests simulations were carried out using Abaqus software. The non-linearity effect caused by structural imperfection/buckling of unit-cell was incorporated. From the compressive test simulation, it was confirmed that the results showed good agreement with the referred experimental data. This means that the developed FE model can be regarded as an RVE model of aluminum foams. Then, the deformation characteristic and elastic modulus obtained from all simulations were compared and examined. As the results, the elastic modulus obtained from bending test demonstrated higher value than that of under uniaxial loads. This discrepancy increases gradually as the relative density decreases. The mechanism responsible for generating the discrepancy in stiffness was discussed. Furthermore, this work points out the necessity of measuring both Young’s and flexural moduli for designing an engineering structure using foam materials especially when accuracy and precision are demanded.
On the Use of Steel and Aluminum Materials for Frame Structure of Electric Trike
This work investigated the pros and cons of aluminum material used for electric trike frame compared with steel material. With a compact design and small dimension, e-trike is suitable to be used in many relatively small road accesses. However, the compact design can cause the frame to receive high and concentrated stress. The aluminum-based frame had lower strength, but lighter weight compared to the steel-based frame. In this study, the stress evaluation for both aluminum-based and steel-based frames is done using the finite element method. The minimum thickness of the aluminum-based frame was iterated to match the strength of the steel-based frame. The results showed that the aluminum-based frame has comparable performance to the steel-based frame but with lighter weight. However, the production cost of the aluminum-based frame might be a challenging issue to be solved.
The application of adsorptive stripping voltammetry for a study of the reaction of human serum albumin with anti-human serum albumin
Abstract Adsorptive stripping voltammetry has been used to study the interaction of human serum albumin with anti-human serum albumin. The adsorptive stripping voltammetric behaviour of both proteins has been optimised with respect to accumulation potential, accumulation time and scan rate. It has been demonstrated that adsorptive stripping voltammetry can be a useful technique for the study of the interaction of these two proteins directly in solution.