Improved metallurgical manufacture via multiaxial testing of microstructures

Next-generation metallurgical manufacturing requires a new level of understanding of how metals and alloys deform under multi-directional loading. The project will address this critical knowledge gap by developing a miniature bi-axial mechanical testing apparatus for in-situ studies inside a scanning electron microscope (SEM). Deformation of materials is often modelled on their uniaxial test characteristics. However, many modern metal-forming processes subject alloys to very complex loading regimes. The limited practical understanding of plastic deformation under multi-axial loading can place constraints on the geometry of the manufactured components. Bi-axial testing provides valuable insight about the intricate deformation mechanics of these processes. The constructed miniature load-frame will be used to investigate microstructure-level deformation of selected high-performance structural alloys in order to characterise component-scale deformation. Digital image correlation and crystal orientation mapping (electron back-scatter diffraction, EBSD) will be used to measure the degree to which deformation is localised at the different microstructural features of the alloys. The studies will identify distinctions between uniaxial and bi-axial deformation behaviour in modern microstructurally complex alloys produced via conventional and additive manufacturing techniques. The results will be used to develop new theories for the deformation of different types of alloy microstructures. These improved models will enable the development and optimisation of novel resource-efficient metal-forming and additive manufacturing processes that produce lighter components with superior structural integrity.