FEM Simulation On The Two-pass Continuous Cold Rolling Of Oval Profile 304 Stainless Steel Wire

Stainless steel is a kind of steel which has certain chemical stability when in the air, water, acid, alkali and salt solution, or other corrosive media. Along with social development, business to wire stainless steel demand has risen sharply, but the direct used was mostly the special-shaped stainless steel wire. So it is need to make deep processing in order to obtain the required specifications of various special-shaped stainless steel wire. The deep processing includes drawing and rolling. Rolling plays a vital role in the final product quality.In the process of shape rolling, it is of vital significance to analyze the deformation of materials such as spread and elongation for the design of proper roll grooves and pass sequences. Furthermore, it is also very important for the analysis of the defect of materials and the improvement of the rolling process. Profile metal deform complexly when be rolled, so it is very difficult to rely on mathematical calculation to get the result of metal flow, stress and strain. The integration of computational mechanics and numerical simulation has greatly reduced the difficulty of the research on rolling process. The finite-element code ANSYS, which is emerging with the development of computer can be suitable for solving the large contact and highly non-linear question. With the increase in the number of the use of Finite Element Method in the rolling process, there have been many examples, which use it in the research of the profile metal rolling process. Although the FEM is widely used in the steel rolling process, the use of FEM in wire rod rolling process is still very little.The two-pass continuous cold rolling process of oval profile 304 stainless steel wire is simulated with the code of ANSYS/LS-DYNA in this paper. The simulation results are summarized as follows: (1) The distribution of internal stress when rolling: the maximum stress appears in the hearts of the workpiece and reduces by round in the out. (2) The distribution of internal strain when rolling: the maximum strain appears in the hearts of the workpiece and reduces by round in the out. (3) The distribution of stress and strain change little when change the friction coefficient or reduction, but the values increase. (4) In both pass of rolling, the internal residual equivalent stress is small at the two diagonals, and large near the width and height radius. The maximum stress appears at the height endpoint; the maximum of residual equivalent strain appears in the hearts of the workpiece and reduces by round in the out. (5) The residual equivalent stress and strain increase a little when the friction coefficient increases, and increase obviously when the reduction increases. (6) The variation of the speed and rolling force of workpiece along with time is obtained. Also the forward and backward of the workpiece is calculated. (7) The spread coefficient and pressure ratio is calculated, and the comparison of result spread coefficient, compression ratio with experiment data shows good agreement. It shows that the problem of shape rolling can be analyzed by code of ANSYS/LS-DYNA.