With the progress of iron and steel production technology, the quality of hot rolled steel sheet has improved significantly in recent years, but in recent years, surface defects of hot rolled steel sheet still occur frequently in China, especially the more serious warpage defects have become a major factor affecting the qualified rate of hot rolled products. The research of hot-rolled steel sheet production technology - dip-rolling-roughing-finishing-coil. The occurrence of elongated Alice skin on the side of high strength alloy steel sheet is 3.68% of the production of high strength alloy sheet pile manufacturers.
From the basic characteristics of macro and micro warpage, the causes of warpage defects are analyzed and discussed in detail. Statistical research is carried out through on-site production, and the adjustment scheme of process parameters is finally made into hot-rolled steel plate. The rate of skin defect of Banqiao was significantly reduced.
After a series of experiments, the following conclusions are drawn.
The part of Alice's protuberance has fallen off the skin. The cracks on the surface of the steel plate retracted by EDS analysis, which confirmed the trace of iron oxide, flux residue and manganese silicate in the gap.
When casting flux is involved in the formation of skin pore, the main causes of skin warping defect of hot rolled steel plate are the falling off of refractory in heating furnace, oxidation at high temperature and pressing into oxide skin of steel rolling mill.
Reducing argon flow rate at die outlet, controlling casting speed and casting stability, adopting appropriate die powder and strictly controlling rolling process and related operation can significantly reduce or even eliminate surface defects of warped hot rolled steel plate.
