Experimentation and modelling in micro drawing of low-carbon steel wires

Research activities on micro-forming have shown that the interactions between material, lubricant and forming tools substantially differ from those of macro-forming. Aimed at the development of models suitable for bulk micro-forming processes, the authors focus the research on micro wires drawing. This process can be considered a quasi-stationary process where material flow and tribological conditions at the interface between workmaterial and die can be assumed to be constant during the whole deformation. Therefore the determination of correlations between material behaviour, die-material interface and process parameters, is more straightforward if compared with three-dimensional or non stationary forming processes. The paper presents the main results of the experimental and numerical campaign on 300 μm wires aimed at: i) performing small reduction (few tens of μm) by fine wires drawing, ii) investigating different material models for surface and bulk layers by the measurement of UTS, as well as grain structure analysis.