The application of a systematic approach to material selection for the lightweighting of metro vehicles

Abstract

With reduced operational energy consumption as the primary driver, a cross-industry consortium of vehicle manufacturers has explored some of the issues surrounding the introduction of lightweight materials into metro vehicles. Taking today's vehicles as the starting point, the aim of the study was to examine the current barriers that need to be removed or overcome in order to realize the economic and environmental benefits of lightweight materials. From a technical perspective, the use of a systematic approach to material selection is described that matches the design requirements and constraints of a given application to potentially suitable candidate materials within a large database. The approach is illustrated by a case study in which a 57 per cent mass saving is achieved for a metro vehicle interior grab rail. Estimates are also provided for the magnitude of the operational energy and cost savings that can be achieved through metro vehicle lightweighting. For the particular scenario considered in this article, a 10 per cent reduction in vehicle mass was estimated to equate to a 7 per cent saving in energy consumption and a corresponding 100 000 € annual operational cost saving per vehicle. Such data can now be used to support decision making with respect to the benefits of lightweighting.