1997 Volume 83 Issue 8 Pages 485-489
High-speed cold rolling of stainless steel strip are attempted in a cluster type mill with small-diameter work rolls, or in a tandem cold-rolling mill with large-diameter work rolls. Surface brightness of the strip deteriorates with high-speed rolling, or with large-diameter work rolls. Authors found that the surface brightness was strongly affected by microdefects on the surface, and the brightness was improved with decreasing surface area ratio of micro-defects. A groove formed of intergranular corrosion is one of the micro-defects on SUS304 steel strip.
In this study, effect of conditions in annealing, pickling and cold rolling on occurrence of the grooves is investigated, and the mechanism for the occurrence of the grooves is discussed. The grooves by intergranular corrosion occurred in cooling of strip immediately after annealing, and the depth and width of the grooves were enlarged in pickling. Occurrence of the grooves was related to layer of insufficient chromium. The grooves flattening on the surface of cold rolled strip were affected by the diameter of work rolls, surface roughness of the roll, and the reduction in thickness. The effects of rolling speed and of viscosity of the rolling oil were little under the experimental conditions investigated.
