Abstract
Keywords: lightweight subframe, hybrid solution, thickness optimization, composite material
In the last few years, the automotive product have been significantly evolved on the pushing of tighter safety requirements and, on the other hand, of market demand towards more complete equipments and accessories. This resulted in a significantly growth of car masses and therefore of consumptions and emissions.
For that reason, the European Commission in agreement with Automotive Industry (ACEA), have decided to introduce norms finalized to the reduction of consumptions and emissions: for the produced range of each OEM, targets have been delineates to gradually reduce the CO2 pollutions in the next years (CAFE 2012 and over).
In order to face such limits, in addition to researches on engines and transmissions efficiency, Centro Ricerche Fiat is currently engaged to improve the total efficiency of the vehicle mainly through the light weighting and the improvement of aerodynamics. In particular, light weighting is fundamental for the achieving of 2012 targets (130 g CO2 / km).
To meet the goal, it will be necessary to obtain considerable lightening (about 80 ÷ 130 kg). Only a multi - material approach could assure the structure lightening with costs/benefits ratio more favorable than mono material solutions (light alloys or composites) (Belingardi et al, 2004; Jambor et al, 1997).
In this scenario, the present activity has been developed through a cooperative study by CRF and Politecnico di Torino. In particular the aim of the work is to design a new lighter engine subframe, without affecting the performance. The target is a reduction of about 30% in weight while requirements to be considered are static and dynamic stiffness, crash behaviour, fatigue, repairability and compatibility with current assembly line.