Reduction of adhesion formation during forming and blanking by influencing thermoelectric currents externally

在DFG项目“通过影响热电电流的无润滑剂成形”中，通过适当水平的外部恒定补偿电流，可以将干下料过程中的粘连形成减少多达30%。在这个项目的范围内，这种减少磨损的新方法现在将进一步开发用于工业实施，以便将来可以在每一个成型和切割过程中使用，甚至减少更多的数量。由于工具中发生的温度和热流主要由工具和板材材料的热电行为和机械性能决定，因此现有数据库将首先扩展到包括新材料和参数。在对不同材料组合下的精密、常规冲裁和拉深工艺进行实验研究中，测量了干燥和不同润滑条件下的所有相关工艺变量。在此基础上，调整外部补偿电流的过程和水平以适应各自的工艺，以实现最大可能的粘附减少。将所得结果与先前项目的结果相结合，推导出一个分析模型。这种方法可以在不了解复杂的相互关系的情况下选择适合各自过程的补偿策略。已知的数据，如速度曲线，力曲线，机械和物理材料性能和选定的工艺参数被用作输入变量。与一种用于活性元件和金属板的通用电接触系统一起开发，该方法可以在未来在新的和现有的工业工具中轻松且经济有效地实施。最后，通过在两种工业工具上的应用证明了该方法的改进潜力。因此，润滑油、电流和工艺温度之间的相互作用为润滑摩擦学系统的研究开辟了新的领域。

In the DFG project "Lubricant-free forming by affecting thermoelectric currents", adhesion formation during dry blanking could be reduced by up to 30% by means of an external constant compensation current at an adapted level. Within the scope of this project, this novel method for reducing galling is now to be further developed for industrial implementation, so that it can be used in future in every forming and cutting process with even higher quantity reductions. Since temperatures and thermocurrents occurring in the tool are primarily determined by the thermoelectric behavior and the mechanical properties of tool and sheet materials, the existing database will first be expanded to include new materials and parameters. In experimental investigations of the processes precision and normal blanking as well as deep drawing with different material combinations, all relevant process variables are measured both dry and under different lubrication conditions. On this basis, the course and level of the external compensation current are adapted to the respective process in order to achieve the greatest possible adhesion reduction. An analytical model is derived from the combination of the findings obtained with those of the previous project. This approach enables the selection of a compensation strategy adapted to the respective process without knowledge of complex interrelationships. Known data such as velocity profiles, force curves, mechanical and physical material properties and selected process parameters are used as input variables. Together with a universal electrical contacting system for active elements as well as sheet metal, which is to be developed, this method can be implemented easily and cost-effectively in new and existing industrial tools in the future. Finally, the improved potential of this method is demonstrated by its use in two industrial tools. Thereby, the interaction between lubricant, current and process temperature opens up new fields of research in the field of lubricated tribological systems.