Additively manufactured suspension components for an F1 car

Abstract

The recent possibilities given by additive manufacturing in free shape design have been seen as a
potential breakthrough in the design and production of structural components of a racecar and more
generally their influences on the future lightweight strategies in the automotive industry is expected
to influence the next generation of products. Among the emerging techniques for the production of
metal products, Direct Metal Laser Sintering (DMLS) and Selective Laser Melting (SLM) technologies
are becoming technically ahead of the competition: the possibility of direct production of aluminum
and titanium alloys components with good surface finishing and net shape from CAD geometry is
nowadays a concrete option for the mechanical designer.
The purpose of the present study is to demonstrate the feasibility of thementionedAMtechniques
and to exploit their potentialweight saving opportunities in the design of highly structurally optimized
racing components while determining the current state-of-art of AM for metallic components. The
present project reports the design and production of two car components redesigned in the perspective
of the novel manufacturing techniques.
The first component is the rear top wishbone bracket of the rear suspension. The production
has been developed following the best practices for the design of additively manufactured structures
such as complete topology optimization and a reconstruction with special focus on the design for
manufacturing assessment. The bracket has been developed for DMLS manufacturing in titanium
alloy Ti6Al4V. On the contrary, the second component has been developed in a novel aluminumalloy:
the Scalmalloy, commercial name of a high strength aluminum alloy specifically developed for high
strength to weight critical applications. For this novel material a characterization campaign has been
set up comprehending tensile testing, micro-graphical analysis, tomography inspection and an X-ray
analysis. Both component underwent a full scale fatigue testing.
Both components proved an achievement in terms of weight saving between 7% and 10%with the
same functionality and performance level of the machine counterparts. The material characterization
campaign revealed the concrete maturity of the DMLS process for Ti6Al4V while the process of SLM
production of Scalmalloy requires some final tuning. The tensile strength levels achieved are compliant
for both materials’ specifications but the presence of localized lack of fusion in the Scalmalloy
specimens reduced the final ductility of the material considerably.
The obtained results are an encouraging step towards the application of the analyzed technology
in structural components for the motorsport industry and possibly, in the near future, for the wider
automotive industry. The limited standardization in the quality processes is addressed as well with
a concrete proposal for establishing a controlled level of defects in additively manufactured components.