Work

The Influence of Process and Slag Parameters on the Liquid Slag Layer in Continuous Casting Mold for Large Billets

Year: 2025

Type: article

Abstract: In the continuous casting of special steel blooms, low casting speeds result in slow renewal of the molten steel surface in the mold, adversely affecting mold flux melting and liquid slag layer supply, which may lead to surface cracks, slag entrapment, and breakout incidents. To optimize the flow and heat transfer behavior in the mold, a three-dimensional numerical model was developed based on the VOF multiphase flow model, k−ϵ RNG turbulence model, and DPM discrete phase model, employing the finite volume method with SIMPLEC algorithm for solution. The effects of casting speed, argon injection rate, and mold flux properties were systematically investigated. Simulation results demonstrate that when casting speed increases from 0.35 m·min−1 to 0.75 m·min−1, the jet penetration depth increases by 200 mm and meniscus velocity rises by 0.014 m·s−1. Increasing argon flow rate from 0.50 L·min−1 to 1.00 L·min−1 leads to 350 mm deeper bubble penetration, 10 mm reduction in jet penetration depth, 0.002 m·s−1 increase in meniscus velocity, and decreased meniscus temperature due to bubble cooling. When mold flux viscosity increases from 0.2 Pa·s to 0.6 Pa·s, the average liquid slag velocity decreases by 0.006 m·s−1 with a maximum temperature drop of 10 K. Increasing density from 2484 kg·m−3 to 2884 kg·m−3 results in 0.005 m·s−1 higher slag velocity and average 8 K temperature reduction. Comprehensive analysis indicates that optimal operational parameters are casting speed 0.35–0.45 m·min−1, argon flow ≤ 0.50 L·min−1, mold flux viscosity 0.2–0.4 Pa·s, and density 2484–2684 kg·m−3. These conditions ensure more stable flow and heat transfer characteristics, effectively reducing slab defects and improving casting process stability.

Source: Crystals

DOI: 10.3390/cryst15050388

Authors: Zhijun Ding, Chao Wang, Xin Wang, Pengcheng Xiao, Liguang Zhu, Shuhuan Wang

Institutions: North China University of Science and Technology, HBIS (China), Hebei University of Science and Technology

Language: English

Topic: Metallurgical Processes and Thermodynamics

Subfield: Mechanical Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,534

Funder: National Natural Science Foundation of China