Control of scale effects in the localized anodic oxidation of aluminium based materials – lokO

阳极氧化层广泛用于铝产品的磨损和腐蚀保护以及其组件的装饰目的。这些弹性层是电化学制造的。到目前为止，整个阳极氧化过程要么是在大规模上实现的，要么是在局部实现的，在这种情况下，需要在电解浸渍浴中进行广泛的掩蔽。对于金属和塑料等多种材料的复杂部件或组件，不应对所有子区域的表面特性（例如磨损、摩擦和硬度）进行阳极氧化，因为这可能会引起不希望的损坏效应。如果要进行阳极氧化的区域的尺寸是灵活可变的，则只能排除由此产生的塑料损坏。由于缺乏资源和能源效率高的工艺，在组件上生成局部氧化层尚不可能。此外，众所周知的是，多相铝基基材材料带来了与工艺相关的挑战，并且需要定制的阳极氧化策略。由于电解自由射流的应用，局部阳极氧化层的制造是可行的。使用电解自由射流的电化学加工代表了电化学过程的本地化技术，迄今为止，该技术已被用于电化学材料去除，即所谓的射流-ECM。第二个项目周期的总体目标是研究和实验实现均匀的、几何形状清晰的表面结构，该表面结构具有对广泛的工业铝合金的高摩擦负荷的抵抗力。通过增加基于喷射的阳极氧化的局部化，将产生局部多孔的阳极氧化物层。局部氧化物斑点的层厚应至少为5 µm，以超过细分的亚微米级和微米级金相成分的尺寸。此外，在非均匀变形合金上形成均匀氧化物应通过模拟辅助控制结构成分的转变行为来实现。

Anodic oxide layers are widely established for the wear and corrosion protection of aluminum products as well as for decoration purposes of their components. These resilient layers are manufactured electrochemically. So far, the whole anodizing process has either been realized on a large scale or locally, in which case extensive masking was required, in an electrolytic immersion bath. Regarding complex components or assemblies of several materials such as metal and plastic, anodizing should not be performed for the modification of the surface properties (e.g. wear, friction, and hardness) of all subareas, since it might induce undesired damaging effects. The resulting damage of the plastic can only be excluded if the dimensions of the areas which are to be anodized are flexibly variable. Due to the lack of resource- and energy-efficient processes, the generation of local oxide layers was not yet possible on components. Furthermore, it is well-known that multi-phase aluminum-based substrate materials entail process-related challenges and require customized anodizing strategies. The manufacture of local anodic oxide layers is feasible due to the application of the electrolytic free jet. Electrochemical machining using the electrolytic free jet represents a technology for the localization of electrochemical processes, which has thus far been used for electrochemical material removal, the so-called Jet-ECM.The overall goal of the second project period is the investigation and experimental realization of homogeneous, geometrically sharp-contoured surface structures with high resistance against tribological load for a wide range of technical aluminum alloys. By increasing the localization of jet-based anodizing, locally porous, anodic oxide layers are to be produced. A layer thickness of the local oxide spots of at least 5 µm shall be realized to exceed the dimensions of finely divided, sub-microscaled and microscaled, metallographic constituents. In addition, the homogeneous oxide formation on inhomogeneous wrought alloys shall be realized through simulation-assisted control of the transformation behavior of the structural constituents.