Numerical Simulation Research On Multi-point Forming Of High-strength Steel

In recent years, with the continuous development of production technology, high-strengthsteel has been used more and more widely in the fields of manufacturing. The mechanicalproperties of high-strength steel are quite different from ordinary carbon structural steel.Because of its high yield strength, high tensile strength, low ductility and plasticity, thetraditional die forming and hand forming due to the high cost and low accuracy of the product isnot the best solution to such issues as high-strength steel forming.Multi-point forming is a new flexible sheet metal forming technology. It takes discreteelements group with regularly arranged instead of forming die. Due to its fast, flexible anddigitized forming characteristics, it has a more bright future in the sheet metal forming field. Inthe forming of high-strength steel, multi-point forming has the advantage such as formingwithout die, deformation path optimization, springback control, forming large parts with smallequipment and easy to implement automation which traditional forming methods don’t have.But by the effects of high-strength steel mechanical properties and multi-point forming technicalcharacteristics, forming process will inevitably encounter the forming defects such as wrinkling,springback. This article will use numerical simulation method to study the wrinkling andspringback defect during multi-point forming of high-strength steel. The research is to study amarine high strength steel.In the research on the wrinkling, by comparison with ordinary carbon steel08AL, it can beconcluded that wrinkling of high-strength steel is smaller than that of ordinary carbon steel. Fordifferent specifications of high-strength steel, thickness increasing will raise unstable limit whileradius increasing will reduce the compressive stress. They’ll make the wrinkle defects decreasesultimately. There are a variety of measures can suppress wrinkling, for example: narrowingelement size, using the elastic pad or spring steel pad, adopting multi-channel formingtechnique.Analyzing the data of formed parts after force unloading, determine the springback curves and values, as the research standard on springback. The results show that: deformationresistance of high-strength steel is greater than ordinary carbon steel, which makes much morespringback after unloading. Since the elastic strain of the sheet is a function of the relativebending radius R/t, with increasing bending radius and decreasing thickness, elastic strain aswell as the springback values after unloading will increase. In order to scontrol the springbackof high-strength steel, combined with multi point forming process, we can use elements groupreverse compensation method. According to the values of springback, adjust the height ofelements group to compensate springback. After testing, this measure can effectively control thespringback and improve the molding accuracy.According to the research conclusion above, appropriate measures can be taken to dealwith the forming defects in the high-strength steel multi-point forming, which will make themulti-point forming technology play its great potential in the forming of high-strength steel.