| 摘要 |
PROBLEM TO BE SOLVED: To provide a cold-rolled steel sheet, wherein the residual stress which is a primary factor for causing deformation accompanying with thermal strain is reduced as much as possible when heating and holding a punched material. SOLUTION: After straightening the cold-rolled steel sheet which is paid off from a pay-off reel 1 with a leveler 2, light reduction rolling 5 is applied to the steel sheet at the draft of 0.2-1.0 and offered to a punching work 3. Then, the residual stress generated at the straightening with the leveler is removed by performing light reduction rolling after the straightening with the leveler and, after that, even when the steel sheet is heated to and held at a certain degree of temperature, the deformation with the thermal strain owing to the release of the residual stress does not occur. COPYRIGHT: (C)2007,JPO&INPIT
|
