Decreasing Porosities in Continuous Casting Thick Slab by Soft Reduction Technology.

Autor: Jiang, Min, Yang, En-Jiao, Hou, Ze-Wang, Wang, Xin-Hua
Předmět:
Zdroj: Metallurgical & Materials Transactions. Part B; Aug2021, Vol. 52 Issue 4, p2753-2759, 7p
Abstrakt: In this study, porosities in thick slabs were successfully decreased by soft reduction technology coupled with an optimal secondary cooling process. Heat transfer calculation showed that asynchronous solidification occurred in the slab when unreasonable secondary cooling was used. As a result, a W-shaped solidification frontier was formed with two liquid craters near the edges of the solidifying slab. Because of a higher solid fraction in the slab width center, compression of the slab was hindered in the soft reduction and porosities could not be efficiently decreased. Under optimal secondary cooling, viz., with intensified cooling water in the 1/4 width regions while weakened cooling in the 1/2 width region of the slab, a W-shaped solid–liquid frontier was greatly impaired. As a result, effective compression can penetrate into the slab center in soft reduction and porosities are remarkably decreased. Measurements showed volumes of porosities in the 1/4 width and 1/2 width regions of the slab were greatly decreased from 9.063 × 10−4 to 2.679 × 10−4 cm3/g and from 2.695 × 10−4 to 1.728 × 10−4 cm3/g, respectively. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index
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