Analysis of slab temperature and stress under single roll heavy pressing for extra thick slab
DU Yi-zhe1,2, LI Li1,2, WANG Qin-zheng1,2, CHEN Deng-fu1,2
1. College of Materials Science and Engineering, Chongqing University, Chongqing 400030, China;
2. Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials, Chongqing University, Chongqing 400030, China
Abstract：In order to obtain the influence of different reduction on slab temperature, stress and strain during heavy reduction, and to evaluate the tendency of corner and internal crack, the solidification heat transfer model of ultra heavy plate was established by using secondary cooling software of slab continuous casting, and the stress-strain model of single roll heavy reduction was established by Abaqus finite element software. The temperature distribution and stress-strain behavior of medium and extra thick plate were studied by numerical simulation. The results show that the surface temperature of the slab will be reduced by heavy pressing, and the decrease of the central temperature is about 1.4 times of that at the corner. The results show that the stress distribution of the slab along the thickness direction presents symmetry along the center, the stress decreases from the inner and outer arc to the center, and the temperature in the corner is the lowest and the stress is the largest. When the reduction increases from 5 to 30 mm, the maximum stress in the corner increases from 84 to 170 MPa, and the tendency of corner cracks increases. In the range of 5~30 mm reduction, the maximum equivalent plastic strain at the solidification front of the slab is less than the critical strain, so there is no internal crack in the slab.
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