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Material extrusion technology is considered to be an effective way to realize the accurate and integrated manufacturing of high-performance metal diamond tools with complex structures. The present work aims to report the G4 binder that can be used to create metal composite filament loading high concentrations of large diamond particles through comparative experiments.

The quality of filaments was evaluated by surface topography observation and porosity measurement. And the printability of filaments was further studied by the tensile test, rheological test, shear analysis and printing test.

The results show that the G4 binder exhibits the best capacity for loading diamonds among G1–G4. The L4 filament created with G4 has no defects such as pores, cracks and patterns on the surface and section, and has the lowest porosity, which is about 1/3 of the L1. Therefore, the diamond-containing composite filament based on G4 binder exhibits the best quality. On the other hand, the results of the tensile test of L5–L8 filaments reveal that as the diamond content increases from 10% to 30%, the tensile strength of the filament decreases by 29.52%, and the retention force coefficient decreases by 15.74%. This can be attributed to the formation of inefficient bonding areas of the clustered diamond particles inside the composite filament, which also leads to a weakening of the shear strength. Despite this, the results of the printing test show that the diamond-containing composite filament based on the G4 binder has reliable printability.

Therefore, the G4 binder is considered to solve the most critical first challenge in the development of diamond-containing filament.

Architectural, engineering and construction (AEC) project organizations are under constant pressure to improve the mental health of project management practitioners (PMPs) due to complexity and dynamism involved in project management practices. Drawing on institutional theory, this research explores how external environmental factors, political factors, economic factors, social factors, technological factors, environmental factors and legal factors (PESTEL), influence mental health management indicators that contribute to positive mental health.

Purposive sampling method was used to collect survey data from 82 PMPs in 60 AEC firms in Australia. Structural equation modelling was used to test the hypotheses based on 82 items of data collected from PMPs.

Overall, this study revealed interesting findings on the impact of external environmental factors on mental health. The hypothesized positive association between political factors and mental health management indicators was rejected. The data supported the proposed hypothetical correlation between economic factors and mental health management indicators and the influence of social factors on mental health management indicators. Moreover, a hypothetical relationship between technological factors and mental health management indicators was supported. The significant positive impact of environmental factors on mental health management indicators proposed was supported, and legal factors’ positive correlation on mental health management indicators was also supported.

Despite the limitations, the present findings suggest that all the external environment factors except political factors shape mental health management outcomes.