Effect of deformation of thin strip material leveling process residual stress - research for improvement of residual stress quality of thin strip product Ⅰ

摘要

In order to evaluate the residual stress of thin strip material after roller leveler in terms of the deformation of the strip, the effects of the working curvature and leveling tension on residual stress are examined using copper alloy sheet material with a thickness of 0.15 mm and proof stress of 43OMPa after tension leveling process. The working curvature of the strip imposed on work roll of the leveler is estimated based upon the image of the strip in contact with the work roll recorded by a CCD camera. Residual stress is estimated by measuring the residual curvatures after successively removing the surface part of the specimen which if cut out from the test material. Numerical simulation of leveling process is also conducted to obtain the theoretical solution of the residual stress. The results obtained here are as follows: (1) Compressive residual stress with the same order of leveling tension is uniformly formed to a certain depth of the strip. (2) The depth coincides with that of the plastic deformation region through the leveling process. (3) The compressive residual stress level increases with large tension loss through the leveling process.