Pioneering friction stir additive manufacturing of steels

Dr Ehsan Farabi has recently joined the mineAlloy team at Deakin University. Ehsan is a physical metallurgist with interest in developing processing-structure-property links for advanced structural materials, mainly steels and titanium alloys. He has expertise in state-of-the-art characterisation techniques, such as electron microscopy (SEM), electron backscattered and transmission diffraction (EBSD and TKD), focused-ion beam (FIB), transmission electron microscopy (TEM). Ehsan specialises in the analysis of complex microstructures, combining experimental results with physical and metallurgical principles. His research is focused on the development of new alloys for advanced manufacturing. This includes understanding and predicting material behaviour, phase transformations, and microstructure evolution during material processing. Ehsan’s current project involves a fundamental study of the process-structure-property relationship of advanced steels during friction stir additive manufacturing (FSAM).

Chun Kit completes project on direct laser deposition of WC/Co

Chun Kit Sit has submitted his Master’s thesis on Direct Laser Deposition (DLD) of WC/Co cermets as wear-resistant coatings. WC/Co cermets are composite materials composed of tungsten carbide (ceramic) in a cobalt binder (metallic). WC/Co cermets are especially hard and wear resistant but their traditional manufacturing processes are expensive.

Direct laser deposition (DLC) of WC/Co is an alternative route for the fabrication of wear-resistant surfaces and it also opens the possibility of repairing used components. This is a particularly interesting option since the wear resistant material can be placed where it is most required, while the bulk of the component can be made from cheaper or tougher materials.

This thesis reports the process optimisation of DLD of WC/17Co coatings on a low carbon mild steel substrate and examines the wear performance of the coatings in both low-stress (ASTM B65) and high-stress (ASTM B611) wear tests.

Refinement of primary carbides in hypereutectic high-chromium cast irons

mineAlloy researchers from University of Queensland and Weir Minerals have recently published a review paper on the refinement of primary carbides in hypereutectic high-chromium cast irons. High-chromium cast irons (HCCIs) are widely used in mining, minerals and cementation industries. The large volume fraction of coarse primary carbides (M7C3) imparts excellent wear resistance, but it also results in high cracking susceptibility and early failure of components, particularly under impact loading. The mechanical performance of HCCIs is correlated with the microstructure of the matrix, as well as the size, shape, volume fraction and distribution of primary carbides. This paper comprehensively reviews the currently available methods to modify the primary M7C3 carbides in various HCCIs and, ultimately, to optimise their mechanical properties for wear resistant applications.

Follow this link to the full paper: