عنوان مقاله [English]
In this paper, the amount of spring-back after 3- roll bending and the effect of different factors such as friction, lateral roller position, roll speed, and thickness reduction percentage of rolling sheet prior to bending on the spring back ratio of aluminum alloy sheet in ambient temperature have been investigated. For this purpose, simulation and finite element roll forming model is done by ABAQUS. In order to validate, a comparison between simulation data and experimental results was performed. To obtain the equation for precise prediction of the values of bending radius after spring-back using SPSS software, regression analysis of the radius values after the spring return obtained from finite element simulation has been studied. Then, the effects of factors affecting bending radius and spring-back ratio have been discussed. The results show that with the method presented in this paper precise prediction of the effect of roll bending parameters changes on spring-back ratio can be obtained. In the following, this technique is used to produce shells with two different curvatures. This method can be a very suitable alternative for bending in the mold or stretch forming in the production of a weld shell and the body of the aircraft.
 M. Chudasama, H. Raval, An approximate bending force prediction for 3-roller conical bending process, International journal of material forming, vol. 6, no. (2), 2013, p. 303-314.
 M. Firat, Computer aided analysis and design of sheet metal forming processes: Part II–Deformation response modeling, Materials & design, vol. 28, no. 4, 2007, pp. 1304-1310.
 W. Gan, R. Wagoner, Die design method for sheet springback, International Journal of Mechanical Sciences, vol. 46, no. 7, 2004, pp. 1097-1113.
 A. Gandhi, H. Gajjar, H. Raval, Mathematical modelling and finite element simulation of pre-bending stage of three-roller plate bending process, in ASME 2008 International Manufacturing Science and Engineering Conference collocated with the 3rd JSME/ASME International Conference on Materials and Processing, American Society of Mechanical Engineers, 2008.
 T. Yu, W. Johnson, Influence of axial force on the elastic-plastic bending and springback of a beam, Journal of Mechanical Working Technology, vol. 6, no. 1, 1982, pp. 5-21.
 W. Johnson, T. Yu, On springback after the pure bending of beams and plates of elastic work-hardening materials-III, International Journal of Mechanical Sciences, vol. 23, no. 11, 1981, pp. 687-695.
 B. Chongthairungruang, et al., Experimental and numerical investigation of springback effect for advanced high strength dual phase steel, Materials & Design, vol. 39, 2012, pp. 318-328.
 M. Hua, D. Sansome, K. Baines, Mathematical modeling of the internal bending moment at the top roll contact in multi-pass four-roll thin-plate bending, Journal of Materials Processing Technology, vol. 52, no. 2, 1995, pp. 425-459.
 M. Chudasama, H. Raval, Bending force prediction for dynamic roll-bending during 3-roller conical bending process, Journal of Manufacturing Processes, vol. 16, no. 2, 2014, pp. 284-295.
 Z. Zhang, et al., A refined model of three-roller elastoplastic asymmetrical pre-bending of plate, Journal of Iron and Steel Research, International, vol. 21, no. 3, 2014, pp. 328-334.
 A. Gandhi, H. Raval, Analytical and empirical modeling of top roller position for three-roller cylindrical bending of plates and its experimental verification, Journal of materials processing technology, vol. 197, no. 1, 2008, pp. 268-278.
 Z. Feng, H. Champliaud, Modeling and simulation of asymmetrical three-roll bending process, Simulation Modelling Practice and Theory, vol. 19, no. 9, 2011, pp. 1913-1917.
 D. Ellis, mechanical properties of aluminum alloys at various temperatures, atomics international. div. of north american aviation Inc., Canoga Park, Calif, 1960.
 H. Quan, H. Champliaud, Z. Feng, T. Dao, FE Study for Reducing Forming Forces and Flat End Areas of Cylindrical Shapes Obtained by the Roll-Bending Process, Journal of Mechanics Engineering and Automation, vol. 4, 2014, pp. 467-475.
 R. Karimi, Statistical Analysis Software Easy Guide of spss. 1394. p. 220.