High-resolution characterisation of secondary carbideprecipitation in martensitic steels

Research Project, 2018 – 2019

The purpose with this project is to broaden the work made in a related project called “Framtidens materialdesign”, which couples high-resolution microscopy with computational techniques in order to validate tools for alloy development. Special focus in that work is on the early stages of carbide precipitation, which gives certain experimental difficulties since the carbides are normally just a few nanometers in size. Martensitic steels are often hardened by the precipitation of these small carbides, and in previous work both transmission electron microscopy (TEM) and atom probe tomography (APT) have been used, and the results have been compared with predictions using tools such as Prisma (by Thermo-Calc). The aim of the proposed work is now to provide additional and missing information on carbide precipitation. For instance, in-situ experiments of carbide precipitation during continuous heating are of interest. In addition, using methods like small angle neutron scattering (SANS) provides average data from large volumes that complements more local measurements techniques like TEM and APT.