Finite Element Simulation of Variable Height Roll-Die Forming Thermal Mechanical Coupling for DP980 Ultra High Strength Steel

It is the development direction that the light weight of automobile.The variable section member of ultra high strength steel can reduce the mass under the condition of certain load. Flexible roll-forming has the advantages of low cost and high efficiency. This paper combined the advantages of rolling and stamping forming, taking the way of roll-die bingding to constraint plate mould with fixed die. Through multi stands rollers which moving along the trajectory of the die,target parts achieve high precision.In order to reduce the forming force and improve the forming quality, the plate material is formed with the local heating. By high temperature tensile test machine obtained the mechanical properties and stress-strain curves of DP980 at different temperatures. Based on thermal and mechanical coupled analysis method, DP980 was the research object. A finite element simulation analysis model of variable height roll forming with local heating is built in ABAQUS. We obtained the distribution of temperature field and stress field at normal temperature and 450℃. The results show that the forming effect of DP980 is good at 450℃ by comparing and analyzing the data. There is no defect such as edge wave, flaws, etc.