摘要
The tensile behavior and properties of cold formed low-carbon microalloyed steel with its microstmcture of all ferrite and pearlite （F ＋ P） were investigated. Bending and flattening deformations were carried out in the laboratory on hot-rolled sheets in order to simulate the cold forming process of steel sheets during pipe fabrication and sampling of high frequency straight bead welding pipes. A comparison of the tensile behavior and properties of the material made before and after cold forming indicates that cold deformation alters the tensile behavior and properties of the material to a certain degree depending on the manner of the cold deformation and the degree. The research on the Bauschinger effect indicates that for the steels investigated, when the plastic strain is small, the back stress increases rapidly with the increase of the plastic strain and then rapidly tends to saturation. The finite element analysis indicates that the change in the properties of the steel sheets due to cold forming is a result of the Banschinger effect and work hardening. The mechanism of the change in the properties is also given in this study.
The tensile behavior and properties of cold formed low-carbon microalloyed steel with its microstmcture of all ferrite and pearlite （F ＋ P） were investigated. Bending and flattening deformations were carried out in the laboratory on hot-rolled sheets in order to simulate the cold forming process of steel sheets during pipe fabrication and sampling of high frequency straight bead welding pipes. A comparison of the tensile behavior and properties of the material made before and after cold forming indicates that cold deformation alters the tensile behavior and properties of the material to a certain degree depending on the manner of the cold deformation and the degree. The research on the Bauschinger effect indicates that for the steels investigated, when the plastic strain is small, the back stress increases rapidly with the increase of the plastic strain and then rapidly tends to saturation. The finite element analysis indicates that the change in the properties of the steel sheets due to cold forming is a result of the Banschinger effect and work hardening. The mechanism of the change in the properties is also given in this study.
