In this work, one-pass and two-pass friction stir processing (FSP) were applied to the tungsten inert gas (TIG) weldments of AA6082-T651 and AA8011-H14 to analyse the microstructure and tensile characteristics of the weldments. The tests included macrostructure, microstructure, microhardness, tensile testing and fractography. When the one-pass and two-pass FSP were applied to the TIG weldments, the coarse grain structure (grain size 24.63 µm) was transformed into a refined grain structure (grain size 2.632 µm for second pass), thereby eradicating the defects that had been seen before FSP. The tensile strengths of the TIG + FSP passes were more significant than that of the TIG welded joints. The ultimate tensile strength of TIG welding, TIG + FSP 1-pass and TIG + FSP 2-pass were 86.86 MPa, 133.833 MPa and 135.75 MPa, respectively. The tensile strain of the TIG + FSPed joints was found to have a minimal difference from that of the TIG welded joints, with the TIG joint with a higher percentage. The joints’ microhardness post-FSP was more significant than the TIG weldment. The maximum hardness (73.84 HV) at the Nugget zone (NZ) was observed in the TIG + FSP 2-pass welded joint. The results obtained corresponded with the grain sizes of the welded joints; the TIG results displayed a coarse-grained structure, while the TIG + FSP results, regardless of the passes, showed a fine sandwich-arranged grain structure.

The study reported in this article aimed to deepen the understanding of the mechanisms driving the adoption and usage of solar photovoltaic (PV) systems in rural Malawian households, particularly among communities that have not received prior solar energy interventions. It used a qualitative approach to investigate the experiences of solar PV system adopters in Ntchisi, Malawi. The study included fourteen participants, and data were collected through observations and interviews, which were then analysed using thematic analysis procedures. The study’s findings indicate that many individuals in rural areas have installed solar PV systems that lack adequate training, resulting in potentially hazardous installations. The installation of solar PV systems in villages is motivated by several factors, including the lack of electricity, convenience, benefits, and personal interest in learning more about solar systems. The participants have highlighted numerous benefits of using solar energy, such as reduced costs, increased convenience, improved productivity, reliable energy access, and telecommunication services. However, solar PV systems are primarily limited to household lighting, phone charging, and powering televisions and radios; however, not for cooking purposes. The findings imply that governments in sub-Saharan Africa should provide training and guidance on the safe and effective use of solar PV systems, invest more in solar PV infrastructure to enable larger solar systems for cooking, refrigeration, and irrigation, and promote the use of solar energy through education and awareness campaigns to encourage greater adoption of solar energy.

Renewable energy mini-grids are considered a cost-effective way to provide electricity for a large proportion of the population in developing countries who do not have access to it. Compared with standalone home systems and national grid systems, mini-grids can potentially offer a better service. They can be deployed faster, making them essential for sustainable development, especially in rural and semi-urban areas of developing countries. However, mini-grids often face challenges regarding their resilience, and many fail to survive beyond their pilot phases. This paper aims to identify the factors contributing to the success of mini-grids and to identify common themes that can help existing and future mini-grid developments become more resilient and influence policy decision making. To achieve this goal, we developed a database of the status of mini-grids in Malawi, with the energy generation resource(s) of their installed capacity, enabling factors, and challenges. We undertook a more detailed investigation of two hydro mini-grid systems—Bondo and Chipopoma. We collected qualitative and quantitative data through literature reviews, site visits, interviews, and observations. The study identified 19 mini-grids with a combined installed capacity of 26 MW. Of these, seven had been abandoned, and one was under development. Several factors that affect successful mini-grid efficacy in Malawi were identified, including financial resourcefulness, technical resourcefulness, policies and regulations, community engagement and capacity building, cross-sector linkages, and institutional organisational frameworks. These factors need to be integrated into decision making by all stakeholders to ensure the enhancement of resilience and the sustainable development of mini-grids.

This article reports on a qualitative multi-case study exploring the challenges mechanical engineering students experience during work placement. The study collected data from 34 purposively selected mechanical engineering students. It found that constraining learning environments, ineffective industry mentors, low quality work affordances and negative student characteristics can compromise students’ work placement learning outcomes. It suggests that the coupling of ineffective mentors and constraining learning environments tends to be associated with low quality work affordances. Industry mentors were considered ineffective if they could not perform the dual role of work supervisors and teachers. It further suggests that some student attributes can also compromise work placement learning outcomes. It found that students who are not proactive or assertive often experience low quality work affordances. To remedy these shortcomings, universities should provide pre-placement training for students and industry mentors in the form of a seminar for industry mentors and simulated work placement for students.

This paper proposes a qualitative systems dynamics model that explains how students’ work placement experiences either enhance or hinder the growth of their occupational competency and self-efficacy. The model is developed from qualitative analysis of work placement experiences of mechanical engineering students from a South African university of technology. Findings from the analysis show that students’ occupational competency and self-efficacy could be considered emergent outcomes of interactions of the learning environment, mentor posture, mentor capacity, mentor availability, meaningfulness of work, scope of work, agency, doing work, co-participating, participation trajectory and performance trajectory. The explanation of the factors and social mechanisms that influence students’ occupational competency and self-efficacy that is offered by the qualitative systems dynamics model would enable the implementation of work placement programs in a manner that would promote rather than hinder the growth of these two indicators of student employability.

Purpose: The study compares how work-integrated learning (WIL) placement positioning, duration, assessment strategies and environment at three Southern African universities influence engineering students' academic and employability outcomes.Design/methodology/approach: The study used a qualitative case study approach that drew on the principles of collaborative autoethnography (CAE). The researchers reflected on WIL placement practices, structure, assessment, environment and outcomes at their universities and then analysed the reflections using comparative descriptive techniques.Findings: The study reports no uniformity among the universities in positioning WIL placement in the curriculum. It is done during end-of-year vacations, between the penultimate and final year or in the last year. The study found WIL placement positioning does not influence academic outcomes; however, the influence on employability outcomes needs further investigation. Components of WIL placement assessment are similar, presentations, logbooks and reports. However, there are differences in the weightings of the various assessment components and the contribution of the industry supervisor. There is a growing trend towards placing students within universities to mitigate the challenges of limited opportunities of placements available in the industry. The impact of this also needs to be further investigated. Lastly, there are policy-related challenges in placing international students. Work restrictions on student visas limit international students’ access to WIL placement. Southern African universities need to lobby the waivers to student visa restrictions that limit their participation in WIL programs if there are to succeed in their internationalisation efforts.Originality/value: The study highlights the gaps in understanding Southern African universities' WIL placement practices, particularly relating to the positioning of WIL placement in the curriculum, the assessment methods used and the theory to work integration and employability outcomes.