| The present study reports the principles of a new system, "equal-channel angular sheet extrusion (ECASE)", which has been designed and manufactured for continuous processing of IF-steel sheets. IF-steel sheets with 1.2 mm thickness and 200 mm width were processed using this system following route-A up to eight passes at room temperature. Microstructural evolution and mechanical properties were investigated as a function of number of passes. The ECASE process increased considerably both σy and σUTS values of IF-steel sheets. sy after one pass was nearly twice as high as that of the as-received one. After eight ECASE passes, the sy and sUTS reached to about 499 MPa and 525 MPa, respectively, which were 2.6 times and 1.9 times higher than those of the as-received ones. However, the processed sheets show limited tensile ductility, which needs to be enhanced with further appropriate processes for them to be utilized in practice. It can be concluded that the use of ECASE provides a simple and effective procedure for improving the strength of IF-steel sheets. |
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