New method for testing plastic damage in alloys

Researchers from Australian’s Nuclear Science and Technology Organisation (ANSTO) have formulated new ways of testing how alloys suffer plastic damage.

The method studies dislocations present in the microstructure of the material and can estimate a component’s service lifetime.

The team, led by Dr Ondrej Muránsky, used Electron Back-Scatter Diffraction (EBSD) and High-Resolution Synchrotron Diffraction (HRSD) to see how materials were affected after being subjected to stress.

The research is a result of a collaboration between ANSTO and colleagues in Canada and the US.

Using the EBSD and HRSD techniques, and a unique Matlab code, the researchers can estimate the theoretical level of plastic damage.

As part of the research, the team compared imaging techniques with the EBSD technique and found the this technique was more sensitive to small amounts of plastic damage. The HRSD technique, in contrast, could better estimate higher amounts of plastic damage.

“Such behaviour highlights the complementarity of EBSD and HRSD when attempting to quantify dislocations (plastic damage) in a material that has experienced an unknown amount of accumulated plastic damage during service,” said Muránsky.

While ESBD measurements were done at ANSTO’s microscopy facility, the HRSD measurements were conducted at the Advanced Photon Source at Argonne National Laboratory in the US. Once a new Advanced Diffraction and Scattering beamline is built at the Australian Synchrotron, in Melbourne, HRSD will be able to be conducted locally.