Research On The Sheet Flexible Deep Drawing Using A Magnetorheological Fluid (MRF)

With the rapid development of modern technology, the lightweight requirements for the parts become more stringent, many kinds of new forming processes become increased, and the sheet flexible forming as a kind of advanced manufacturing technology has gained widely attention. According to the difference of their attribute, the sheet dielectric pressure forming mainly includes hydroforming, viscous medium forming and solid particles forming, due to their characteristics of limited technology, the traditional flexible medium forming process always exists some technical bottleneck and limits the generalization and application.Under this background, in this paper, attempts were expanded; the paper regarded the MRF, which was one of the typical intelligent materials, as the transmission medium to form sheet. Under the action of the magnetic fields, the MRF had the comprehensive advantages and characteristics of the solid, semisolid and liquid and other transmission mediums, and exhibited certain performance characteristics such as rheological behavior and time-varying, which could achieve quantitative controllable load on the corresponding parts of forming sheet and had an important effect on the wall thickness distribution, forming limit, springback and the degree of sticking mode in the sheet deep drawing process.Firstly, the group of magnetic medium and the transmission force characteristics had been in-depth studied, and determined the required model of magnetic medium through theoretical analysis. The magnetic field distribution characteristic was analyzed in the sheet deep drawing by using the finite element software named ANSYS, reveals the law of the punch diameter, electrical current and the number of windings on the influence of the magnetic field distribution, finally, the optimal process scheme was obtained.Finally, the self-developed drawing forming experiment device based on the magnetic medium pressure was studied, and compared and analyzed the forming performance differences of the parts between the conventional drawing and the magnetic medium under the action of the different electrical current. The research results showed that: with the increase of electrical current, before the magnetic medium did not reach the magnetic saturation, the magnetic medium pressure gradually strengthened, the wall thickness distribution in the deep drawing process was more uniform, the difference of the wall thickness Distribution was significantly reduced in the each site of the sidewall, the boundary circle height was significantly reduced, when the current increases to 2 A, compared with the conventional deep drawing,the forming limit increased by 26.3 % and the springback and the wrinkling defect had been significantly improved, the he springback reduced from 2.9 mm to 0.2 mm the warping height decreased by 33.8 %, Enhanced magnetic field made the cylindrical member better in the corner of the parts in the sheet deep drawing using the MRF,the forming quality had been significantly improved.