The shift to remote learning during the COVID-19 pandemic presented a unique challenge for higher education in developing countries such as South Africa, where resources are distributed unevenly. The Department of Chemical Engineering at a South African university of technology used a flipped classroom blended online learning approach in an engineering mathematics course. This study describes the transition of first-year engineering students from face-to-face learning to flipped classroom blended online learning. The Laurillard conversational framework for teaching learning was used to develop the five components of blended learning pedagogy, this allows students to discover, learn, practice, collaborate, and assess (DLPCA). The chosen assessment strategies made use of adaptive learning technology via the WebAssign platform to provide formative and summative assessments as well as timely feedback to each student. The authors examined the remote teaching and learning approach using three indicators: (i) learning—students’ learning experiences; (ii) assessment—students’ academic performance and integrity; and (iii) students’ challenges. The findings had a positive impact on students’ learning and performance in the mathematics course. The limitation to the study was that the data were collected only from one university of technology and were not compared with other universities in the country. The overall findings of this study indicate that students require time to adjust to online pedagogy to ensure a smooth transition.

The occurrence of high temperatures in combustion chambers of jet engines and gas turbines has led to the demand for new technologies and new materials for the manufacture of one of the most critical elements of these systems - the turbine blades. These elements have to withstand extreme temperatures for extended periods without loss of mechanical strength, conditions under which many alloys fail. Such failure is ascribed to the combination of high temperatures and high centrifugal forces, resulting in creep. This is especially prevalent in multi-crystalline structures in which grain boundaries present weaknesses in the structure. High temperature resistant alloys formed as single crystal (SX) structures offer the necessary material properties for safe performance under such extreme conditions. Modelling and simulation techniques were first used to study the directional solidification (DS) of crystal structures during vacuum investment casting. These models allowed the study of the dendritic growth rate, the formation of new grains ahead of the solid/liquid interface and the morphology of the dendritic microstructure. These studies indicated the opportunity to optimise the velocity of the solidification front (solidification rate) for single crystal structures. The aim of this study was therefore to investigate the effect of the solidification rate on the quality of SX castings. The investigations were carried out for nickel-based superalloy CMSX-4 turbine blade casts and rods using the Bridgman process for vacuum investment casting.

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