特厚钢板射流淬火过程厚向冷速实验研究

利用特厚钢板射流淬火试验装置,研究了15~35℃水温、1.0~3.0 m/min辊速对特厚钢板厚向冷速的影响,分析钢板在不同温降区间内的厚向温降、温度梯度和冷速影响因素.利用导热微分方程,采用反传热法计算钢板淬火温度场和冷速.结果表明:采用射流冲击淬火方式时,160 mm钢板心部冷速大于1.2℃/s;水温和辊速除影响钢板表面平均传热系数和换热形式外,还通过改变厚向温度梯度分布影响厚向冷速;水温或辊速升高,钢板厚向冷速降低,降低幅度与冷却强度、淬火时间以及钢板内部导热特性有关.

Experimental Study on Thickness Cooling Rate of Jet Impingement Quenching for Ultra Heavy Plate

The effects of water temperature(15~35℃) and roll speed(1.0~3.0m/min) on the thickness cooling rate of jet impingement quenching for ultra heavy steel plate are experimentally investigated. The temperature decrease，temperature gradient and the factors of cooling rate along thickness direction in difference sections of the plate are analyzed. Using the inverse heat conduction method to solve the differential equation of heat conduction， the quenching temperature field and cooling rate of the plate can be calculated. The results indicate that the cooling rate of the 160mm steel core is greater than 1.2℃/s under the jet impingement quenching， and water temperature and roll speed affect not only the average heat transfer coefficient and the type of heat transfer near the plate surface， but also the thickness cooling rate by changing temperature gradient distribution. The thickness cooling rate decreases when water temperature and roll speed increase， and the decreasing range of cooling rate depends on cooling intensity， quenching time and thermal conductivity of the plate.