Design and optimization of Metallic Foam Shell protective device against flying ballast impact damage in railway axles. (November 2020)

• Record Type: Journal Article
• Authors: Epasto, Gabriella; Distefano, Fabio; Gu, Linxia; Mozafari, Hozhabr; Linul, Emanoil
• Is Part Of: Materials & design. Volume 196(2020)
• Publication Date: 2020-11
• Subjects: Protective sandwich structure -- Railway axle -- Ballast impact behaviour -- Non-destructive evaluation -- Finite element analysis; Materials -- Periodicals; Engineering design -- Periodicals; Matériaux -- Périodiques; Conception technique -- Périodiques; Electronic journals; 620.11
• DOI: 10.1016/j.matdes.2020.109120
• Languages: English
• ISSNs: 0264-1275

Abstract

Abstract: Ballast impacts can initiate surface defects that cause abrupt failure of the axle and derailment of the railway vehicle. According to the Federal Railroad Administration the axle and bearing failure costs around 89 million dollars and causes 46 derailments in the US per year (2005–2010). In this study, the authors have suggested a novel protective mechanism (Metallic Foam Shell – MFS) by using a lightweight sandwich panel. At the first step, a preliminary study is conducted, followed up by the numerical simulations to determine the applicable materials. At the next step, experimental tests were performed to assess the efficiency of the suggested device against flying ballast impacts. An extended non-destructive (NDT) evaluation has been performed in order to find the most suitable technique for damage detection of the proposed device when on-service. The studied cases were GFRP and Aluminium sandwich panels, having an aluminium foam core with different densities and thicknesses. The results showed that the MFS can absorb up to 90% of the initial impact energy and significantly decrease the chance of rebounding impact to the other components. Moreover, the results were also analysed in order to propose the most reliable NDT method for this specific application. Graphical abstract: Unlabelled Image Highlights: A novel Metallic Foam Shell (MFS) protective device against flying ballast impact damage in railway axles is designed. By using impact tests and non-destructive evaluation methods, the most optimal MFS configuration is proposed. The newly developed MFS device can absorb up to 90% of the initial impact energy with total protection of the axle. The suggested MFS device can be effectively evaluated by means of the most common non-destructive techniques.