This paper presents the response of the technology teacher education programmes at the University of Limerick to the assessment challenge created by the shift in philosophy of the Irish national curriculum from a craft-based focus to design-driven education. This study observes two first year modules of the undergraduate programmes that focused on the development of subject knowledge and practical craft skills. Broadening the educational experience and perspective of students to include design based aptitudes demanded a clear aligning of educational approaches with learning outcomes. As design is a complex iterative learning process it requires a dynamic assessment tool to facilitate and capture the process. Considering the critical role of assessment in the learning process, the study explored the relevance of individual student-defined assessment criteria and the validity of holistic professional judgement in assessing capability within a design activity. The kernel of the paper centres on the capacity of assessment criteria to change in response to how students align their work with evidence of capability. The approach also supported peer assessment, where student-generated performance ranks provided an insight into not only how effectively they evidenced capability but also to what extent their peers valued it. The study investigated the performance of 137 undergraduate teachers during an activity focusing on the development of design, processing and craft skills. The study validates the use of adaptive comparative judgement as a model of assessment by identifying a moderate to strong relationship with performance scores obtained by two different methods of assessment. The findings also present evidence of capability beyond the traditional measures. Level of engagement, diversity, and problem solving were also identified as significant results of the approach taken. The strength of this paper centres on the capacity of student-defined criterion assessment to evidence learning, and concludes by presenting a valid and reliable holistic assessment supported by comparative judgements.

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This paper reports on the application of numerical techniques to predict the initiation and propagation of central burst defects in the wire drawing process. The development and implementation of a suitable failure model into a commercial finite element code, via a user written subroutine, has enabled the occurrence of ductile fracture by central bursting in 2011 Aluminium alloy wire to be successfully analysed. In validating the numerical model, the drawing force, die pressure and occurrence of central burst defects has been compared with previously published experimental data. Results from the numerical model suggest that a 'nose shape' curve divides the safe and unsafe zones for the successful drawing of the wire. It follows that no central bursts are expected to occur, regardless of the die angle used, when the reduction ratio is less than a critical value. When central bursts did occur, the effective strain was found to vary periodically along the surface of the wire. These oscillations corresponded with the occurrence of central burst defects and resulted in variations in the final diameter of the wire. These variations in the final diameter of the wire are thought to be representative of an external defect known as 'bamboo markings', which are often an external indication of central burst defects within the wire.

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A new approach for the prediction of central burst defects in extrusion and wire drawing is proposed. Central burst defects are troublesome in industry as it is impossible to detect these defects by simple visual examination alone. It is therefore important to identify the combination of process parameters that will reduce the probability of these defects occurring. The proposed approach is capable of accurately predicting when and where a central burst is likely to occur. The influence of die geometry on damage development and subsequent central burst formation is examined using the modelling capabilities of Abaqus finite element software. The ductile fracture criteria of Cockcroft and Latham, Oyane and Chaouadi were employed using a Fortran subroutine, and their ability to predict the onset and evolution of the central burst defect was examined. For relatively lower area reductions and die angles the considered criteria are capable of accurately predicting the morphology of the defect. Under these conditions, the proposed approach shows good agreement with experimental results, confirming its effectiveness and suitability for industrial application. The failure criteria are inadequate in predicting central burst defect formation during conditions of large reduction in area and large semi-die angles. Further development of ductile failure criteria is necessary to accurately simulate defect evolution for all die angles and area reductions.