جستجوی مقالات مرتبط با کلیدواژه « شکل پذیری » در نشریات گروه « میان رشته ای »

Tube flow forming is one of the most economical production methods for simple cylindrical tubes with external and internal protrusions with or without flanges. The purpose of flow forming operation for body production is to use more raw materials and increase mechanical properties due to hard work on the part instead of raw machining of tubes. Due to the high strength of these tubes, it is one of the most important methods of manufacturing cylindrical bodies in the aerospace industry. In this research, the formability of high-strength maragining steel has been experimentally investigated by the three-roller flow forming process and finite element analysis. The effect of changes in flow forming process parameters such as mandrel rotation speed, feed rate, and angle of attack on dimensional and geometric accuracy as well as surface quality of the produced product was investigated experimentally and numerically. The results showed that the surface roughness of the final product increases up to 62% as the feed rate increases. Increasing the feed rate also leads to the reduction of out-of-roundness by more than 50%, thus improving the geometric quality of the final part. Increasing the rotation speed of the mandrel leads to a decrease in the surface roughness up to 30%. Also, increasing the rotation speed leads to an increase in the non-rotation of the product. Increasing the angle of attack of the roller from 15 to 30 degrees leads to an increase of about 30% in surface roughness and a decrease in non-roundness and a decrease in diameter growth.

Composite shear wall consisting of steel sheet with reinforced concrete cover is one of the most common systems resistant to lateral loads in tall structures. The main purpose of this study is to investigation the effect of reinforced concrete cover, steel sheet thickness, door and window opening on the seismic behavior of steel frame with composite shear wall. For this purpose, in the present study, after validation of numerical modeling, 19 specimens of composite steel shear wall with a height of 3.2m and a span length of 5m are modeled. The results of this study show that the utimate strength, stiffness, dissipated energy and ductility in the model with reinforced concrete cover without opening and with a steel sheet with a thickness of 15 mm, respectively 12.24, 63.78, 7.82 and 4.37 times the reference model and in the same model without reinforced concrete cover, these values are 8, 41.61, 4.46 and 6.24 times the reference model, respectively. In other words, the reinforced concrete cover, due to the prevention of buckling of the steel sheet due to compressive force, has increased the utimate strength, dissipated energy and ductility. Also, in reinforced concrete cover, increasing the thickness of the steel sheet from 10 to 15 mm has little effect on the utimate strength.