Aluminum alloy 6201 is a wrought, heat-treatable alloy, which is used in electricity transmission and distribution lines. The alloy is processed in a commercial continuous casting and rolling system, which includes a series of in-line thermomechanical processes involving hot working, quenching, cold working and artificial aging. In this study and following cold working, the alloy is subjected to a solution heat treatment at 510 °C for an hour, quenched in ice water, and artificially aged at various temperatures for various times (150–200 °C for 2–30 h) (T6-temper) in order to investigate the effect of precipitation on mechanical properties and electrical conductivity. The results show that optimum mechanical properties and electrical conductivity were obtained after artificial aging at 155 °C for 30 h (155-30). The tensile strength was almost equal to that of the as received cold drawn wire of 326 MPa, but interestingly, electrical conductivity significantly increased to 58.6% IACS from a value of 52.7% IACS of the as received cold drawn wire. Intermetallic particles α-AlFeSi (Al₈Fe₂Si) and β-AlFeSi (Al₅FeSi and Al₉Fe₂Si₂) were observed in all samples, which were nucleated during solidification and homogenization; they were not affected by the aging process. β″/β′/β -precipitates formed during artificial aging, which affected the final mechanical properties and the final electrical conductivity.

Pipelines are the main method of oil and gas transportation due to economics and safety. However, the use of carbon steel as a material type has led to the introduction of pipeline defect assessment due to the increased probability of corrosion threat. Several assessment methods have been developed over the years to assess corrosion defects in pipelines. Corrosion defects can occur in pipelines internally or externally in the form of single or clustered defects. As the distance between two corrosion defects decreases, they will begin to interact reducing the failure pressure compared to when they are treated as single defects. Although there have been studies on this subject, oil and gas pipeline operators are still faced with inconsistencies with the decision upon which closely spaced defects can be clustered as single defects. In this work, the influence of surface location (internal or external) and depth on defect interaction were analyzed using finite element analysis and further compared with analytical methods. The pipes were modeled with curved boxed defects at different spacing and orientations to simulate actual metal loss defects. Comparison of the results showed conservatism in the existing analytical methods which may result in unnecessary shutdowns, repairs, and operating below the required parameters. The numerical results showed that defect surface location (internal or external) and depth has a great influence on the defect interaction and predicted failure pressure.

In this study, the finite volume method was used to evaluate the thermal performance of a flat-plate solar collector used to dry agricultural crops. A 3D numerical model was created and used to predict the outlet air velocities and temperatures for three inlet air velocities. When compared with experimental measurements, the numerical predictions showed good agreement under all testing conditions. Then, the numerical model was used to predict the internal airflow and heat transfer characteristics of the collector. The internal baffles were found to increase the dwell time and efficiency but also promote flow separation, which resulted in flow loss. In addition, the collector has a transparent cover that results in a substantial heat loss, which can be mitigated by adding a vacuum gap between the flow inside the collector and the cover. Increasing the flow rate increased the heat loss and decreased the heat uptake, which decreased the temperature difference between the inlet and outlet of the collector. Because the heat was lost through long-wavelength radiation via the transparent cover and sidewalls, coating the absorber plate with black matte paint to increase the solar radiation absorption coefficient did not improve the drying performance.

Polypropylene (PP) is one of the leading polymers in the polymer industry finding applications from automotive industry to medical equipment and adding silica can make it more desirable. A lot of experimental analysis has been done to study the effect of particle size among other parameters on PP/silica composites. However, very few literatures numerically analyze PP/silica composites. This study focuses on developing a 3D Finite Element based homogenization model that can accurately predict the elastic mechanical properties of PP/micro-silica composites. A Repeating Unit Cell is deployed during this study and periodic boundary conditions are imposed. The contribution of the model was demonstrated by comparing experimental results to the numerical analysis. The maximum error between the two for the Young’s modulus was less than 4% for 3% micro-silica composite. Similarly, to predict the compressive modulus, the maximum error was less than 7%. Parametric study was conducted to demonstrate how the proposed model behaves better than the analytical micro-mechanic models for soft materials like polymer composites and where contact failure occurs between the matrix and particle.