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Abstract: Existing tests for assessing the formability of sheet metal samples can create strain ratios in the range from uniaxial to biaxial stretching, −1/2≤ ɛ 2/ɛ 1 ≤1. A novel sample design is proposed, with shaped cut-outs in a rectangular sheet specimen, intended to produce with strain ratios in the range, −1≤ ɛ 2/ɛ 1 ≤1/2 in a small zone, while the sample is uniaxially extended. The strain ratio is controlled by changing the geometry of the cut-outs. The behaviour of the new sample design is examined by finite element modelling showing nearly proportional behaviour in the test zone, with the best results occurring near to pure shear. Two experimental methods are considered for the validation of these predictions: measurement of the distortion of a grid of small circles created on the sample surface by laser-scribing; use of a commercial strain measurement system based on an applied speckle pattern. Both techniques demonstrate that the evolution of experimentally measured strains during the test closely follows that predicted numerically. The novel sample is applied to test the formability of a range of materials known to be difficult to form. The tests on aluminium alloys Al 2024, Al 7075, Al 2198 and commercially pure titanium demonstrate that significantly enhanced deformation prior to failure is possible with loading near to pure shear. The implication of these results is that it may be possible to design novel forming processes capable of creating more dramatic deformation in “difficult to form” materials through the creation of strain paths close to pure shear. [Copyright &y& Elsevier]

Abstract: This review presents a thorough survey of academic work on the analysis and application of the mechanics of spinning. It surveys most literature published in English and the most important publications in German and Japanese languages. The review aims to provide insight into the mechanics of the process and act as a guide for researchers working on both metal spinning and other modern flexible forming processes. The review of existing work has revealed several gaps in current knowledge of spinning mechanics: the evolution of the stress state and the strain history of the workpiece in both conventional and shear spinning is not well understood, mainly due to the very long solution times that would occur in modelling the process throughout its duration with a sufficiently fine mesh to capture detailed behaviour through the workpiece thickness; the evolution of microstructure, residual stress and hence springback, has not been examined—either numerically or by experiment; the failure mechanisms of spinning – fracture and wrinkling – are only partially understood, through analogy with other processes, and as yet models of the process have not made use of contemporary damage mechanics; the design of toolpaths required to make particular parts without failure remains an art, and cannot currently be performed automatically with confidence. Studies on novel process configurations in spinning have shown that great potential for innovation in spinning exists. The process has the potential to be more flexible, to produce a wider range of shapes, and to form more challenging materials. [Copyright &y& Elsevier]

Abstract: Companies aiming to be ‘sustainability leaders’ in their sector and governments wanting to support their ambitions need a means to assess the changes required to make a significant difference in the impact of their whole sector. Previous work on scenario analysis/scenario planning demonstrates extensive developments and applications, but as yet few attempts to integrate the ‘triple bottom line’ concerns of sustainability into scenario planning exercises. This paper, therefore, presents a methodology for scenario analysis of large change to an entire sector. The approach includes calculation of a ‘triple bottom line graphic equaliser’ to allow exploration and evaluation of the trade-offs between economic, environmental and social impacts. The methodology is applied to the UK''s clothing and textiles sector, and results from the study of the sector are summarised. In reflecting on the specific study, some suggestions are made about future application of a similar methodology, including a template of candidate solutions that may lead to significant reduction in impacts. [Copyright &y& Elsevier]