EDT毛化轧辊表面凹坑形成过程

针对轧辊表面电火花毛化过程中放电中心温度的变化、凹坑形状与电参数的关系等问题进行了研究.通过分析放电通道形成过程和热流密度分布函数,采用解析法建立了单个脉冲放电通道的热传导模型,并运用积分变换法和有限差分相结合的方法进行了温度场求解.讨论了轧辊表面在不同峰值电流下放电区域中心位置的瞬态温度变化,确立了峰值电流和脉冲宽度与熔化凹坑形状的关系.结果表明,理论计算值与实验结果相吻合,所建模型与采用的方法正确,可用于轧辊表面形貌形成过程的仿真.

Process of crater formation upon electric discharge textured roll surface

The problems about the variation in center temperature of discharged region and the relationship between crater shape and electrical parameters in the process of electric discharge texturing on the surface of a work roll was studied. The developing process of discharging channel and the distribution of heat flux were analyzed. A thermal conduction model of single channel spark per pulse was presented. By combining the methods of integral transform and finite difference this model was solved. The change of transient temperature at the center spark point upon the roll surface was discussed under the condition of different peak current, and the relation of crater shape to peak current and pulse duration was also deduced. Finally, the calculated values were compared with the experimental ones. The result showed that they were in good agreement. The developed model and adopted method were valid and could be used for simulation of the developing process of geometric topography on roll surface.