12th Tooling Conference & Exhibition - Tooling 2022

Corrosion-resistant mould steels are used to process chemically aggressive plastics such as PVC or PET in many plastic moulding processes such as extrusion, injection, blow and compression moulding. Free machining (sulfurized) grades are common choice for holders where the requirements are machinability and dimensional stability, whereas low sulfur grades are preferred for high surface finish requirements. But selecting the mould steel composition is not sufficient, the optimal production route is also very important. Research work was carried out on 2083 and 2085 martensitic stainless steels as well as other proprietary grades to increase the reliability and service life of the steel components used in the plastic injection mould industries. The influence of inclusions on the machinability and corrosion resistance in sulfurized or calcium-treated free-machining steels will be discussed.