Composite material components damaged by impact loading: a methodology for the assessment of their residual elastic properties
Journal Title: Journal of Achievements in Materials and Manufacturing Engineering - Year 2018, Vol 1, Issue 87
Abstract
Purpose: Detection and evaluation of damage due to impact or fatigue loading in components made by composite materials is one of the main concern for automotive engineers. We focus on damage due to impact loading on long fibre, plastic matrix composite, as they represent one of the most interesting development solution for automotive components toward lightweight structure that in turn means reduction of fuel consumption and of Green House Gas emissions. Design/methodology/approach: An innovative simplified methodology is proposed, based on the impact and repeated impact behaviour of composite material, for the evaluation of the induced damage and of material residual elastic properties. The investigated composite laminate is made of eight twill-wave carbon fabrics impregnated with epoxy resin. The methodology consists of two phases: at first the identification of the impact response. Composite plates have been impacted at different energy levels and residual elastic properties measured through standard tensile tests. The relationship between impact energy and residual elastic properties is obtained. Then the exploration impact load is identified, large enough to give a well-defined picture of the suffered damage but soft enough to do not induce further damage in the composite laminate. Findings: This exploration impact test and the Damage Index (DI) value, as interpretation key, leads to a prediction of the local residual elastic properties in the damaged area. The proposed methodology has been validated on plate specimens. A strict correlation is found between the predicted and the actual residual elastic properties of the damaged composite plate. Practical implications: Subsequently it has been applied to a composite beam, with a omega shape transverse section, that can be considered as a demonstrator for a typical beam used in the car body frame. Originality/value: A selection on the following alternatives will be possible: a – don’t care the damage is not affecting the structure performance; b – repair is needed but will be sufficient; c – substitute the damaged component as soon as possible.<br/><br/>
Authors and Affiliations
G. Belingardi, M. P. Cavatorta, D. S. Paolino
Contents
Cover
Study on homogeneity and repeatability of single-piece flow carburizing system
Purpose: The purpose of this paper was to determine the homogeneity and replicability of carburized layers obtained by a continuous single-piece flow method. Design/methodology/approach: A series of 100 gears was carburi...
Customer satisfaction study using the Servqual method
Purpose: In this article the application of a part of Servqual method in the selected enterprise was presented. Based on the results obtained key areas to service improvement in the organization were show...
The influence of storage conditions on the physicochemical properties and dimensional accuracy of the alginate impressions
Purpose: Alginate impression materials are the most commonly used masses for taking impressions. They are characterized by good relation of properties to the price. However, the main problem associated with use of the im...
Mechanical properties of Easy Fill composites after storage in mouthwashes
Purpose: The aim of the presented work was to investigate the influence of different mouthwashes on the chosen mechanical properties of different dental restorative composites. The null hypothesis was that the mouthwashe...