LIFE CYCLE MANAGEMENT OF A VEHICLE COMPONENT OR SUB-SYSTEM

摘要

The objective of the study, carried out with ARCELOR Auto, IRSID/ARCELOR and Fiat Auto, is to compare the benefits and drawbacks of various materials solutions for a “B” type vehicle bonnet. Technical and economical performances have been taken into account and enlarged with environmental considerations. The aim was to achieve the best compromise of all these parameters from the product’s design stage.The study focused on the following materials solutions for the bonnets: 1) “monolithic” steel (starting from the traditional “Normal Production” component) 2) aluminium 3) steel sandwich (“USILIGHT”), with two possible alternatives for the outer panel thickness, made of steel and a polymeric material For each material solution, a re-engineering (or, depending on the material alternative, a shape and size optimisation), has been done for the inner reinforcement. Through the “Life Cycle Management” (LCM) approach, intended as the integration between Life Cycle Assessment (LCA) and Life Cycle Costing (LCC), it has been possible to determine the influence of the material alternatives. Then, the assessment of the environmental impacts and costs have been done for all the analysed alternatives, through the application of the LCA methodology and LCC approach. These evaluations have been carried out for the main steps of the bonnets’ life cycles (production, use, end-of-life). Particular attention has been paid to the End-of-Life phase, concerning the recycling considerations and the scrap differentiations between “prompt” and “obsolete” scraps Throughout the whole life cycles of the considered bonnet alternatives, the main results display that: · the environmental impacts are reduced with re-engineering (reduction of the bonnet’s overall mass); · steel solutions (traditional grades and innovative sandwich steel) are “greener” and cheaper than the aluminium solutions. Some interesting conclusions are therefore that it appeared better to keep steel-based solutions (mono-material or steel sandwiches) instead of aluminium, and operate a minimisation of the bonnets’ masses (and, consequently, an environmental impact reduction) through the optimisation of the inner reinforcement.