The effect of precooling on hot ductility of a low‐carbon steel is investigated. It shows a wide reduction of ductility in the temperature range of 700–900 °C with a general hot tensile test. The hot ductility is increased by applying precooling before the hot‐tensile test. The increase in the reduction of area (RA) reaches 40–50% when the steel is precooled to 500 °C. Active precipitation of (Mn, Cu)‐sulfide is observed during the precooling. The increased RA is attributed to the active sulfide formation, which decreases sulfur segregation at grain boundaries.

中文翻译：

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通过预冷提高低碳钢的热延性

研究了预冷对低碳钢热延展性的影响。在一般的热拉伸试验中，它表明在700–900°C的温度范围内，塑性大大降低。通过在热拉伸试验之前进行预冷来提高热延展性。将钢预冷至500°C时，面积减小率（RA）的增加达到40–50％。预冷期间观察到（Mn，Cu）-硫化物的活跃沉淀。RA的增加归因于活性硫化物的形成，从而减少了晶界处的硫偏析。