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This study aims to investigate the performance of filament-based material extrusion additive manufacturing (MEX), combined with debinding and sintering, as a novel approach to manufacturing ceramic components.

A commercial ZrO₂ filament was selected and analysed by infra-red (IR) spectroscopy, rheology and thermo-gravimetry. The influence of the print parameters (layer thickness, flow rate multiplier, printing speed) and sintering cycle were investigated to define a suitable printing and sintering strategy. Biaxial flexure tests were applied on sintered discs realised with optimised printing strategies, and the results were analysed via Weibull statistics to evaluate the mechanical properties of printed components. The hardness and thermal conductivity of sintered components were also tested.

Layer thickness and flow rate multiplier of the printing process were proved to have significant effect on the density of as-printed parts. Optimised samples display a sintered density >99% of the theoretical density, 20% linear sintering shrinkage, a characteristic flexural strength of 871 MPa with a Weibull modulus of 4.9, a Vickers hardness of 12.90 ± 0.3 GPa and a thermal conductivity of 3.62 W/mK. Gyroids were printed for demonstration purposes.

To the best of the authors’ knowledge, this work is the first to apply biaxial flexure tests and Weibull statistics to additively manufactured MEX zirconia components, hence providing comparable results to other additive technologies. Moreover, fractography analysis builds the connection between printing defects and the fracture mechanism of bending. This study also provides guidelines for fabricating high-density zirconia components with MEX.

The purpose of this paper is to determine and quantify the most dominant types of food waste in Hungarian households and to analyse the effect of demographic background and income as influencing factors.

Data related to solid and liquid food waste were recorded from 100 households for one week. The study primarily focussed on avoidable food waste, however, unavoidable and potentially avoidable food waste were also measured. Appropriate tools and manual were provided to the households to ensure data consistency.

Estimated quantity of total food waste (including liquid waste) per capita is 68.04 kg/year. In all, 48.70 per cent of total food waste would have been avoidable (equals to 33.14 kg/capita/year). Most frequently wasted food categories were meals and bakery products. In case of some demographic categories, different wastage levels were observed. It was also confirmed that income has effect on food waste production that varies by foodstuff categories: bakery product waste was mainly dominant for middle income consumers and fresh fruits were typically wasted by more affluent households. Apart from that, higher income resulted in higher food waste production in general.

This primary data set about avoidable food waste in Hungary contributes with relevant information to the refining of international estimates. Having specific data on food wastage and the most affected target groups, as well as information on the impact of the income can be applied in planning awareness raising campaigns.

The research is based on measurement of food waste categories in households resulting in detailed data sets. This study is one of the first investigations based on primary data collection from the eastern part of Central Europe and the very first related to Hungary. The study draws attention also to the influence that household income exerts on the issue of food waste.