高强度硼钢淬火界面热交换系数的实验与模拟

Experiment and simulation on quenching interface heat transfer coefficient of high-strength boron steel

通过测量硼钢B1500HS淬火过程中板料和模具的温度变化曲线,结合有限元分析及反传热模型获得淬火过程中板料与模具间的界面热交换系数（IHTC）与温度的关系。结果表明：板料温度从770℃下降到200℃,IHTC的变化范围在1970~3960 W/（m2·K）之间。随着板料温度的降低,IHTC随之降低,但由于材料在410℃时发生奥氏体向马氏体的转变,相变潜热的释放导致IHTC不连续的现象发生。与以距离模具形面下方1mm处作为淬火介质的环境温度相比,以模具形面处作为淬火介质的环境温度得到的IHTC分布规律同前者基本一致,但IHTC的数值较高。

Interface Heat Transfer Coefficient （IHSC） between blank and tools is the key factor to obtain the temperature field, stress and strain fields and microstructure distribution of boron steel hop stamping parts. By measuring the temperature changes of the blank and die in the process of quenching combined with finite element analysis and the inverse heat transfer model, the relationship between the interface heat transfer coefficient and temperature was obtained. The results show that IHSC ranges from 1970 W/（m2 ~ K） to 3960 W/（m2 ~ K） when the temperature of the blank decreases from 770 ~C to 200 ~C. IHTC decreases as the temperature of the blank decreases. However, the release of latent heat during the transformation from austenite to martensite results in the discontinuity of IHTC at 420 ~C. The distribution of IHTC is almost the same under different environmental temperatures and quenching mediums. The IHTC values of the die surface temperature as quenching medium are higher than those at the location 1 mm below the surface of the die.