Optimal Control of Surface Crack in Microalloyed Steel with Big Stroke Liquid Core Reduction Process

摘要

In this paper, a new idea of optimizing and improving the surface crack of microalloyed steel slab by using big stroke liquid core reduction (B-LCR) process was studied and analyzed by combining numerical simulation with industrial test. The results show that the stress-strain distribution is different in different parts of the slab during liquid core reduction; the stress at the corner of the slab is the largest, and the stress at the wide surface is greater than that at the narrow surface. When the total reduction is increased to 35 mm by using B-LCR process, the equivalent strain on the interior of the slab is 0.566%. It is consistent with the maximum additional strain value (calculated value) of 0.552% on the center of the slab, and no pressure crack will occur. The industrial test results show that B-LCR process can improve the internal and surface quality of low content alloying element steel obviously. But with the gradual increase in microalloying element content, B-LCR process cannot completely solve the surface crack defect. It can only play a role in reducing defects.