連續退火線﹙Continuous Annealing Line，簡稱CAL﹚具有快速和高產能的優點，可大幅降低生產成本，提高產品競爭力。然而所生產的電磁鋼片在沖製剪裁以後會有翹曲的現象。這種現象與鋼帶殘留應力分布不均有關，推測其原因為鋼帶在通過爐輥時產生的彎曲應力以及鋼帶寬度方向不均勻溫度分佈所致。連續退火線內有許多工作區域，本論文研究的部份為預熱區與加熱區，主要是探討鋼帶二維溫度分佈，以及爐內邊界條件。本論文運用熱平衡法與數值計算，並考慮了材料相變化對鋼帶溫度可能造成的影響，求取鋼帶的二維溫度分佈及爐內邊界條件以利爾後進行鋼帶應力分析。模擬結果顯示，在預熱爐時鋼帶寬度方向溫度機無差異；而在加熱爐時，鋼帶中央的溫度高於兩側且溫度差異最大約為40℃，而在加熱爐出口則減少為25℃。

The process of continuous annealing line (CAL) exhibits the advantage of high production rate. Therefore, the cost of production can be significantly reduced and the competition of production can be enhanced. However, the electromagnetic sheet shows the phenomenon of bowing after having cut into pieces. The phenomenon of strip bowing may relate to the non-uniform residual stress distribution of steel strip, which may be introduced by the bending stress as the strip passes through the rollers and non-uniform distribution of temperature and stress of the strip in width. The process of CAL consists of several zones. This study investigates the 2-D temperature distributions of the strip and environment within the preheating and heating furnace. To aid the strip stress analysis, this study investigates not only the 2-D temperature of steel strip but also the boundary conditions in preheating and heating part of CAL with thermal balance method and numerical calculation, and also considers the phase-change of material in higher temperature. According to the simulation results temperature of strip in width almost does not change, but in heating part, the temperature in central part of
the strip is higher than two sides about 40℃ and 25℃ at exit.

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