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Additive manufacturing (AM) can achieve significant weight savings with only minor compromises in strength if high-performance wrought aluminum alloys are used as feedstock. Despite the advantages in strength that aluminum alloys (AA) 6061 offer, they cannot be manufactured via printing because of hot cracking and other solidification problems. The purpose of this study is to achieve high-quality printing of AA6061 with nanotreated wires.

Nanotreating was used to modify the AA6061 alloy composition by adding a small fraction of nanoparticles to enhance the alloy’s manufacturability and resultant properties. Wire arc additive manufacturing (WAAM) was used to print the nanotreated AA6061 wire feedstock. The microstructure of the printed AA6061 was characterized by X-ray crystallography, optical microscopy, scanning electron microscopy and energy dispersive spectroscopy mapping. The microhardness profile, tensile behavior and fracture surface were analyzed.

This work successfully used WAAM to print nanotreated AA 6061 components. The resulting AA6061 parts were crack-free, with exceptional grain morphology and superior mechanical properties. Owing to the excellent size control capabilities of nanoparticles, a homogeneous distribution of small grains was maintained in all deposited layers, even during repeated thermal cycles.

Previous studies have not successfully printed AA6061 using WAAM. Conventional WAAM products exhibit anisotropic mechanical properties. The nanotreated AA6061 was successfully printed to achieve homogeneous microhardness and isotropic tensile properties. The promising results of this study reflect the great potential of nanotech metallurgy as applied to the WAAM process.

The purpose of this paper is to examine the trend of return migration of health professionals to Ghana and how it is impacting the delivery of health services in the country. It also highlights the challenges facing returnees to the country.

A qualitative exploratory case study approach was employed in the study. Data gathered were analysed using the sequential model of qualitative content analysis.

It was found that while push factors dominantly influence out-migration, pull factors rather dominated reasons for return migration. Other determinants of return migration include social and financial benefits to the home country, achieving goals for travelling, skills’ improvement and spousal consideration. The paper also highlights some of the challenges returnees usually encounter in the home country.

This paper makes reasonable recommendations regarding how return migration of Ghanaian health professionals might be smoother.

The study brings to the fore, the necessity for the government to plan for health professionals, who returned to Ghana to contribute to the health system.