SYSTEM AND PROCESS FOR HARDENING SLAB SURFACES BASED ON HORIZONTAL ZONE OF CONTINUOUS CASTING MACHINE

• Main Authors: ZHU MIAOYONG, CAI ZHAOZHEN
• Format: Patent
• Language: English; Japanese
• Published: 17.10.2023
• Subjects: CASTING; CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES; CHEMISTRY; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; PERFORMING OPERATIONS; POWDER METALLURGY; TRANSPORTING

To provide a system and a process for hardening slab surfaces based on a horizontal zone of a continuous casting machine, which reliably avoid the occurrence of cracking due to hot delivery of micro-alloyed steel slabs.SOLUTION: A system for hardening a slab surface based on a horizontal zone of a continuous casting machine includes a hardening bending zone for hardening the slab surface, wherein the continuous casting machine includes a pressure bending zone, the hardening bending zone is located in the rear of the pressure bend zone, and a surface temperature of the slab at an entrance of the hardening bending zone is 930°C or higher.EFFECT: By executing a hardening process on the slab surface by means of the hardening bending zone, which is provided in the rear of the pressure bending zone, a temperature in a range of 0-10 mm under a skin on top and bottom surfaces of the microalloyed steel continuous casting slab undergoing on-line hardening is quickly reduced from 930°C or more to 600°C or less to achieve dispersion precipitation of carbides and structural transition from austenite to ferrite or bainite, thereby radically improving plasticity of the cast slab surface microstructure.SELECTED DRAWING: Figure 1 【課題】マイクロアロイ鋼スラブのホットデリバリーによる割れの発生を確実に回避する、連続鋳造機水平帯に基づくスラブ表面焼入れシステム及びプロセスを提供する。【解決手段】連続鋳造機水平帯に基づくスラブ表面焼入れシステムはスラブ表面を焼入れするための焼入れ湾曲帯を含み、前記連続鋳造機は圧下湾曲帯を含み、前記焼入れ湾曲帯は前記圧下湾曲帯よりも後に位置し、前記焼入れ湾曲帯の入口における前記スラブの表面温度が９３０℃以上である。【効果】圧下湾曲帯よりも後に設けられる焼入れ湾曲帯によりスラブ表面に焼入れプロセスを実施することによって、オンライン焼入れを受けたマイクロアロイ鋼連続鋳造スラブの上面及び下面の皮下０～１０ｍｍ範囲内の温度が９３０℃以上から６００℃以下に迅速に低下し、炭窒化物の分散析出及びオーステナイトからフェライト又はベイナイトへの構造転移を達成させ、鋳片表層組織の可塑性を根本的に向上させる。【選択図】図１