Characterisation of the influence of material hardness in precise electrochemical machining of steel

High wear resistance is one main requirement for highly loaded components. For instance the wear resistance of steel is adjusted specific to its application by help of heat treatment. However the machinability decreases by increasing this steel property. For this reason machining of steel takes place in many cases in uncured state and a finishing process is required to achieve the surface finish and the geometrical requirements of the component after heat treatment. As an alternative machining process precise electrochemical machining (PECM) can be applied to machine wear-resistant steel after heat treatment procedure [1, 2]. The process is based on anodic dissolution with the advantage to remove material less dependent from mechanical properties like tensile strength and toughness [1, 2]. However the removal is highly dependent on the material composition and due to hardening processes a chemical transformation of the material occurs. This transformation will influence the removal process. Therefore in this study the influence of the steel hardness in precise electrochemical machining will be characterised in comparison to the uncured state. The characterisation is performed by help of removal experiments which will be carried out under same process conditions to analyse the electrochemical dissolution characteristics of the steels in dependency to its hardness.