高线辊环精轧过程中热疲劳行为研究

利用有限元的方法,以精轧机用粘结相含量为20wt%的YGR45硬质合金辊环为研究对象,分别对轧制速度分别为40 m/s、80 m/s、160 m/s进行轧制模拟;并结合不同的冷却条件,研究了不同轧制速度下硬质合金辊环在高线热轧过程中的的热行为。结果表明:随轧制速度的增加,辊环温度梯度变小,有效的冷却装置能使辊环的最高温度、平均温度和温差保持不变,而没有冷却装置的则不能。高的温度变化速率是高线精轧辊环表面出现热疲劳裂纹的主要因素。

Research on Thermal Fatigue Behavior of Rolls in Finish Rolling of High-speed Wire Mill

The rolling of the YGR45 grade carbide roll with 20wt%binder content used for finishing mill were simulated at the roll speed of 40 m/s,80 m/s and 160 m/s by means of finite element method.Combining with different cooling conditions,the thermotics behavior of the carbide roll for high-speed wire mill in the course of hot rolling at different rolling speed were studied.The results show that with the increase of roll speed,the temperature gradient in the carbide roll decreases.Effective cooling device can make the maximum temperature,average temperature and temperature difference in the roll remain unchanged.The high temerature variation rate is the critical factor of thermal fatigue crack appearing on the roll surface.