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This paper engages Olaf Zawacki-Richter and Insung Jung in a frank and penetrating conversation that seeks to ground, frame, and problematise research in the field conceptualised as “open, distance and digital education” (ODDE). Taking as starting point the recent publication of the landmark Handbook of Open, Distance, and Digital Education (2022), it segues into a broad critique of the shortcomings of ODDE research, the importance of knowledge production on the meso- and macro-levels, the autonomy of ODDE as a field coming into its own, the place of postfoundationalism in ODDE discourse, and related topics that are pivotal in ODDE today.

The semi-structured interview was employed as the primary qualitative research method.

The research imperative of the relatively young but complex field of ODDE today is not the incessant reiteration of the same but rather a strategic reorientation that, first, circumvents the well-documented yet too-often-overlooked shortcomings of ODDE research and, second, promotes transboundary collaborations with the potential for system-wide impact.

This novel interview-based critique of ODDE research demonstrates that extending the scholarly discourse beyond the conventional report format is a productive method for enriching conversations on ODDE and vitalising the field itself.

The purpose of this paper is to investigate the effect of remelting each layer on the homogeneity of nickel-titanium (NiTi) parts fabricated from elemental nickel and titanium powders using laser powder bed fusion (LPBF). In addition, the influence of manufacturing parameters and different melting strategies, including multiple cycles of remelting, on printability and macro defects, such as pore and crack formation, have been investigated.

An LPBF process was used to manufacture NiTi alloy from elementally blended powders and was evaluated with the use of a remelting scanning strategy to improve the homogeneity of fabricated specimens. Furthermore, both single melt and up to two remeltings were used.

The results indicate that remelting can be beneficial for density improvement as well as chemical and phase composition homogenization. Backscattered electron mode in scanning electron microscope showed a reduction in the presence of unmixed Ni and Ti elemental powders in response to increasing the number of remelts. The microhardness values of NiTi parts for the different numbers of melts studied were similar and ranged from 487 to 495 HV. Nevertheless, it was observed that measurement error decreases as the number of remelts increases, suggesting an increase in chemical and phase composition homogeneity. However, X-ray diffraction analysis revealed the presence of multiple phases regardless of the number of melt runs.

For the first time, to the best of the authors’ knowledge, elementally blended NiTi powders were fabricated via LPBF using remelting scanning strategies.