TP1: Wear, corrosion and fatigue behaviour of functional surfaces produced by high-speed blanking

根据材料和所选择的工艺参数，高速冲裁（HSB）产生的表面可能包含绝热剪切带（ASB）。这些都是均匀的区域，在微观结构方面与基材明确划分，与周围材料相比，表现出明显改变的性能特征，例如更高的硬度。然而，高速冲裁表面的结构-性能关系至今仍未得到充分的研究。因此，子项目1的重点是为HSB表面在摩擦、腐蚀和循环机械载荷下的行为提供科学合理的答案。这直接关系到需要获得对工作机制的基本理解，从而识别过程-微观结构-属性关系。这样做的先决条件是对磨损、腐蚀和疲劳试验结果的解释，这是与研究小组合作伙伴协调进行的，旨在揭示HSB表面特性、工艺参数和所得微观结构之间的相关性。摩擦学研究包括代表不同载荷制度的各种磨损试验。因此，在有或没有中间介质的情况下，系统地研究了平面和弯曲HSB表面在开槽、滑动和滚动载荷下的材料行为。腐蚀行为的表征是跨尺度进行的。一方面，通过浸水和盐雾试验确定了其宏观性能。另一方面，利用微腐蚀池对ASB和周围材料的各个微观组织成分的耐腐蚀性进行了比较评价。此外，通过特殊设计的试样几何形状，研究了在宽应变速率范围（10²- 10 5 s-¹）下产生的ASB的疲劳特性。此外，利用x射线衍射（XRD）测量了HSB表面的残余应力，以评价材料的性能。以这种方式确定的宏观和微观残余应力一方面用于解释摩擦学、腐蚀和循环力学试验的结果，另一方面，它们代表了项目合作伙伴微观结构建模或过程模拟的重要评估和验证变量。子项目1的研究结果为评价HSB表面的使用性能和实际适用性提供了依据。通过与其他子项目的反馈，结果也可以直接影响HSB工艺的设计，从而有针对性地调整功能表面的性能。

Depending on the material and the selected process parameters, surfaces produced by high-speed blanking (HSB) can contain adiabatic shear bands (ASB). These are homogeneous zones, which are clearly delimited from the base material in microstructural terms and exhibit a significantly changed property profile compared to the surrounding material, such as a higher hardness. However, the structure-property relationships of high speed-blanked surfaces have remained largely unexplored to date. The focus of subproject 1 is therefore to provide a scientifically sound answer to the question of how HSB surfaces behave under tribological, corrosive and cyclic mechanical loading. This is directly linked to the need to gain a fundamental understanding of the mechanisms at work and thus the identification of process-microstructure-property relationships. A prerequisite for this is the interpretation of the results of the wear, corrosion and fatigue tests, which is carried out in coordination with the research group partners and aims at revealing correlations between the HSB surface properties, the process parameters and the resulting microstructure. The tribological investigations include various wear tests that represent different loading regimes. Thus, the material behavior of both flat and curved HSB surfaces is systematically investigated under grooving, sliding and rolling loads with and without intermediate media. The characterization of the corrosion behavior is performed across scales. On the one hand, the macroscopic behavior is determined in immersion and salt spray tests. On the other hand, the corrosion resistance of individual microstructural constituents of the ASB and the surrounding material is comparatively evaluated using a microcorrosion cell. Furthermore, by means of specially designed specimen geometries, the fatigue properties of ASB generated in a wide strain rate range (10²–10⁵ s-¹) are investigated. In addition, the residual stresses of HSB surfaces are measured by X-ray diffraction (XRD) to evaluate the material behavior. The macro- and micro residual stresses determined in this way are used on the one hand to interpret the results of the tribological, corrosive and cyclic mechanical tests, and on the other hand they represent important evaluation and validation variables for microstructure modeling or process simulation by the project partners.The research results obtained in subproject 1 are the basis for the evaluation of the service properties and thus the practical suitability of HSB surfaces. By means of feedback with the other subprojects, the results also enable direct influence on the design of the HSB process and thus targeted adjustment of the properties of the functional surface.