Liquid Phase Sintering of High-Alloyed Plastic Mould Steels: Calculations and Experimental Findings on Atmospheric Influences

摘要

Many tool devices are exposed to a combined load of corrosion and wear. Plastic mould steels exhibit a good corrosion resistance provided by a sufficient content of chromium and a good wear resistance due to carbides dispersed in a martensitic matrix. A further gain in wear resistance is achieved by the addition of hard particles to the steel for obtaining a particulate reinforced metal matrix composite (MMC). The common processing route for these MMC is hot isostatic pressing, but they can also be consolidated by solid state or liquid phase sintering.In this work, detailed investigations on the sintering behaviour and resulting microstructures of two plastic mould steels were performed. The experiments were supported by thermodynamic calculations to explain the influence of the sintering atmosphere. The results show an improved corrosion and wear resistance compared to HIP materials, being related to microstructural findings.