Influence of Duplex- tool coatings on the thermomechanical tribological properties during friction spinning of AW 6060 and the generation of a numerical simulation of the friction spinning process

在第一个资助期的基础上，这个后续项目将更详细地分析aw6060成形过程中的摩擦和粘附过程。在此背景下，针对摩擦纺丝刀具开发了双相涂层系统，旨在优化刀具-工件系统的热流，减少刀具磨损，提高工件表面质量。因此，通过应用促进粘附的金属中间层，可以更深入地了解TiBN-PVD薄层在氧化陶瓷热障涂层（TBC）上的粘附机制。分析了摩擦纺丝过程中TiBN顶层对摩擦和粘附性能的相互作用。双相涂层结合了大气等离子喷涂Al2O3或ZrO2-8Y2O3 tbc，并在其表面使用冷喷涂NiCr， Ti或Cr进行金属化。金属化的目的是完全覆盖TBC的表面近孔，从而降低粗糙度，以便通过PVD实现TiBN的近净形沉积。在awa6060成形过程中，刀具的表面粗糙度与黏着磨损密切相关。此外，还将分析优化刀具性能的方法。这些方法包括应用开发的双相涂层，除了应用凹槽和润滑外，还可以改变接触面积的大小。因此，工艺策略是推导出优化热流和减少粘接磨损。第一个资助期的结果证实了摩擦力对温度和相对速度的依赖性。此外，摩擦是否取决于法向应力？由于摩擦纺丝涉及高温、相对速度和常压值，第二个资助期的目标是在真实工艺条件下表征摩擦，以获得可靠的结果。为此，将准备一个实验装置，在摩擦纺丝装置中集成压缩测试，通过工具板移动到旋转的aw6060管上并引发塑性变形。法向力将直接测量，而剪切力将从扭矩测量中计算。所获得的力将用于在此过程中获得对摩擦的扎实理解，并推导出摩擦旋转的可表示摩擦模型。得到的摩擦值将被整合到热-机械有限元模拟模型中，以描述摩擦纺丝过程。然后用实验值对仿真模型进行了温度、力和几何特征的验证。

Based on the first funding period, this follow-up project is concerned with the analysis of the friction-pressing process in more detail with regard to the friction and the adhesion processes during the forming of AW 6060. In this context, duplex coating systems are developed for the friction-spinning tools, which aim to optimize the heat flow in the tool-workpiece system and to minimize tool wear and increase the surface quality of the workpieces. Thus, a deeper understanding of the adhesion mechanisms of TiBN-PVD thin layers on oxide-ceramic thermal barrier coatings (TBC) is generated through the application of adhesion-promoting metallic interlayers. The interactions of the TiBN top layer on the friction and adhesion properties during the friction-spinning process are then analyzed. The duplex coating integrates atmospheric plasma sprayed Al2O3 or ZrO2-8Y2O3 TBCs and a metallization of their surfaces with NiCr, Ti or Cr using cold gas spraying. The aim of the metallization is to completely cover the surface-near pores of the TBC and thus to reduce the roughness in order to achieve a near-net-shape deposition of TiBN by means of PVD. The surface roughness of the tool is correlated particularly with the adhesive wear during the forming of AW 6060.Furthermore, approaches will be analyzed to optimize the tool performance. These approaches include the application of the developed duplex coatings, varying the contact area size in addition to applying grooves and lubrication. Consequently, process strategies are to be derived to optimize the heat flow and to reduce the adhesive wear.The results of the first funding period confirmed the dependency of friction especially on temperature and relative velocity. Furthermore, is friction dependent on normal stress. Due to the fact that friction spinning involves high temperatures, relative velocities and normal pressure values, the target of the second funding period is to characterize friction under real process conditions to obtain reliable results. For this purpose, an experimental setup will be prepared, in which a compression test is integrated in the friction-spinning setup, whereby a tool plate moves onto the rotating AW 6060 tube and initiates plastic deformation. The normal forces are to be measured directly whereas the shear forces will be calculated from torque measurements. The obtained forces will then be used to gain a solid understanding of the friction in this process and to derive representable friction model for friction-spinning. The friction values obtained will consequently be integrated in the thermo-mechanical FEM-simulation model to depict the friction spinning process. The simulation model is then validated with experimental values in terms of temperature, force and geometric features.