Investigation of Production Limits in Manufacturing Microstructured Surfaces Using Micro Coining

Abstract

The application of microstructured surfaces is one possible method to reduce friction in lubricated contacts between components with relative movement. Due to this, the energy efficiency and the occurring wear during the operating time of the final products could be decreased. To manufacture structured surfaces economically, a micro coining process was analyzed within this study. This process offers the potential for integration into the established manufacturing processes of different final products, such as tappets used in a valve train. Thus, large-scale production is enabled. To detect the manufacturing limits of the micro coining process, the manufacturing of the coining tools as well as the coining process needs to be investigated. Within this study, the achievable accuracy and the failure of cuboid and cylindrical microstructure elements with selected dimensions were analyzed. For both types of microstructures, the minimal lateral dimensions were detected. Besides the achievable accuracy, correlations between different geometrical dimensions of the micro elements are presented. Additionally, the aspect ratio is detected as the main cause of failure for the micro coining process. In general, the suitability of a coining process for manufacturing microstructured surfaces is proven.

Investigation on tool properties for the production of components with micro textured surfaces

“…Besides its friction system, the suitability of the tool material 1.3343 for the fabrication of micro texturized punches is analysed. In the design of micro textured surfaces for the use in friction reduction applications of highly loaded lubricated body contacts, the height is a decisive parameter to influence the hydrodynamic pressure and therefore the lubricant's film thickness [1]. The heights of cuboid textures, fabricated by EDM, are accordingly analysed for the high speed tool materials 1.3323 and 1.3244.…”

“…Applying defined microscopic structures on metal surfaces have the potential to reduce friction between highly loaded lubricated components under relative motion [1]. In bioengineering, micro textured surfaces can be implemented to provide antibacterial effects [2].…”

Friction reduction in EHL contacts by surface microtexturing – tribological performance, manufacturing and tailored design

“…The investigation was based on the high-speed steel 1.3343 hardened to 62 ± 1 HRC as a typical representative in cold forging applications. For more details on the selected process parameters and the procedure for creating the textures, refer Zahner et al (2017). With regard to the lateral dimensions, a production limit of 5 µm is determined in Figure 2(a) for the width of the cuboid textures irrespective of the texture heights.…”