球墨铸铁因其优良性能而被广泛用作模具材料。对球墨铸铁冲压模具的激光表面处理已成为改善其耐磨性、提高使用寿命的重要方法。一定激光参量下吸收率的大小又直接影响到表面处理的质量。因此,确定球墨铸铁材料对激光的吸收率十分必要。通过热电偶测温,计算机数据采集系统进行定点温度采集,并结合数值模拟方法,对吸收率进行了标定,即首先根据预置的吸收率计算,预测被测点处的温度响应,并与实测响应比较,不断修正吸收率值,使预测温度响应和实验值吻合,由此获得吸收率。采用这种方法获得了球墨铸铁材料在大气条件下对激光的吸收率为23.3%。为激光处理球墨铸铁材料时工艺参量的选择和优化提供了一定参考。

Ductile iron has been as the materials for stamping and drawing dies due to its good mechanical properties. In recent years, laser surface modification of dies of ductile iron has been an important method to improve its wear resistance and useful life. With laser surface modification, absorptivity influences the surface modification straightly under certain laser parameters. So it is necessary to determine the laser absorptivity of ductile iron. The temperature is measured by thermal couple and treated by computer data-acquisition system. Meanwhile, the numerical simulation is to determine the absorptivity. The simulative temperature response at a certain point can be obtained through predictive absorptivity and compared with that of experiments until the simulated one is coincidence with experimental one. In the result, the absorptivities of ductile iron under atmosphere is 23.3%. It provides some reference for the selection and optimization of technical parameters during the laser material processing.