In-situ Synchrotron Investigations of Additive Manufacturing parts for Ni-base Superalloys

Important results from the project

The goal of this project is to optimize the AM process chain for superalloys for extreme conditions, with the purpose of avoiding cracks in such alloys. Cracking, for this type of alloys, occur during subsequent heat treatment due to mechanisms not yet fully understood. In the project we tried to monitor the evolution of residual stresses during several heat treatment cycles, but it was not possible to a satisfactory degree, at Petra III. For sucessful measurements, a series of separate experiments need to be set up and executed for residual stress measurement and phase development.

Expected long term effects

If new heat treatment recipes were found that prevent formation of cracks, it could unlock a new group of alloys for production via AM. We have not yet achieved this within the framework of the project, but we have taken steps to potentially achieve this goal. Producing gas turbine components, in precipitation hardened superalloys, via additive manufacturing (AM) are of great interest to the industry. Turbine performance could then be significantly improved using e.g. novel cooling designs.

Approach and implementation

WAXS and SAXS patterns give information on the development of phase fractions and precipitate size, as well the induced stress during simulated heat treatments. A new project needs to be defined where separate measurements with SAXS and WAXS are not performed simultaneously. Such an approach requires that heat treatment cycles are repeated for different beamline configurations.