Determination of Circumferential Mechanical Properties of Steel Tube by Ring Tensile Test

• First Author:Zicheng Zhang
• Journal:The 2010 Japanese Spring Conference for the Technology of Plasticity
• Abstract:The TRIP steel tube is a new kind of high-strength steel tube expected to be used in the hydroforming process. It has a good combination of strength and elongation in the axial direction. In order to study the hydroformability of the TRIP steel tube, firstly, its circumferential mechanical properties should be made clear. The ring tensile test is an effective method for obtaining the true stress vs. true strain curve and the anisotropy coefficient value (r-value) of tube in the circumferential direction. In this study, a new kind of ring tensile test equipment was developed to investigate the circumferential mechanical properties of the TRIP steel tube. According to the geometrical and mechanical relationships, the instantaneous load along the circumferential direction can be obtained. The instantaneous vertical distance of the gauge section bob point is measured by an optical camera. The instantaneous gauge section length can be calculated by the instantaneous vertical distance according to the geometrical relationships. To confirm the reliability of this method, the simulation of the ring tensile test was carried out. By analyzing the true stress vs. true strain curve used in the simulation process and the one obtained by calculation using this method with simulation results, it was found that they agree to each other very well. It means that this method is reliable. As a result, the true stress vs. true strain curve of the TRIP steel tube in the circumferential direction was obtained. By the strain grids, the r-value was also obtained.
• Key Words:Circumferential mechanical properties;TRIP steel tube;Ring tensile test;Anisotropy coefficient value;Seamless tube
• Page Number:197-198
• Translation or Not:no