THE CRACKS ON SLAB CORNER DURING HOT ROLLING PROCESS

The slab corner surface transversal cracksand longitudinal cracks during a multi-pass V-H rolling process withplain-barreled vertical roll and shape vertical roll were simulated bythe explicit dynamic finite element method and updating geometric method, andthe effects of vertical roll shapeduring rolling processon crack closure and growth were analyzed. Results show that, when applyingplain-barreled vertical roll during multi-pass V-H rolling process, thedeformation of slab corner crack is large, and it tends to spread,for slab corner transversal cracks, the nodes on crack tip lines maydiffuse outwards, for triangle transversal cracks and longitudinal cracks,one side of crack may be folded; when applying shapevertical roll during multi-pass V-H rolling process, after vertical rolling,the cracks are closed well, after horizontal rolling, the longitudinalcracks and transversal cracks on slab side surface may open again, butthe transversal cracks on slab top surface can be closed well, at the sametime, only triangle longitudinal cracks show the phenomenon that one sideof crack is folded.