Effect of cavity design on textured tool surfaces in sheet metal forming

In order to advance sustainability in manufacturing, it is necessary to reduce both energy use and material waste. Tribology is recognised as a central factor in this effort. In sheet metal forming, for example, friction and wear lead to increased energy demand, tool degradation and lubricant consumption. Therefore, surface texturing has emerged as a promising strategy to improve tribological efficiency, contributing to both technical performance and reduced environmental impact. Building on earlier findings which identified cavity geometry, spatial distribution and load conditions as decisive parameters, this study introduces a systematic methodology for designing surface textures for lubricated forming operations. Computational fluid dynamics is used to analyse the rheological mechanisms underlying lubricant flow and pressure generation in textured interfaces. The optimal cavity design is defined by its ability to minimise the coefficient of friction. The results demonstrate that lubricant reservoirs and hydrodynamic pressure formation depend heavily on cavity dimensions and distribution. In particular, the coverage ratio and lubrication clearance are shown to have the most significant influence on friction reduction. These insights pave the way for more resource-efficient and sustainable sheet metal forming processes by linking tribological performance to reduced energy demand and extended tool life.