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EOS has played a role in helping the University of Warwick to compete in Formula Student, which challenges undergraduates to design and build a single-seat racing car and compete at Silverstone.

Several years ago, an Eosint P 380 was purchased to produce optimised plastic components for the race cars in short time frames.

Last year, for the first time, EOS in its role as technical partner contributed further by manufacturing and supplying laser sintered metal components.

The university also has on site WMG, which owns the EOS plastic processing machine installed in its international manufacturing centre.

The group, which among other functions supports undergraduate and postgraduate projects, has also invested over the years in other AM machines, including stereolithography, fused deposition modelling and EOS’ sand-sintering technology for casting.

In last year’s car, there were three main areas where AM lowered the weight of components compared with the 2009 model.

First, titanium alloy and carbon fibre replaced hardened steel in the production of the half shafts driving the two front wheels.

Second, Inconel was substituted for steel tubing when producing the exhaust header.

Third, laser sintered alumide, an aluminium-filled polyamide 12 powder, was used instead of a casting or fabrication for the induction system.

Looking in more detail at the half shafts, their production used to pose a problem for the university team, as finalisation of their design always came late in the build.

They were previously turned from hardened steel bar of approximately 20mm diameter and then had a circlip groove and splines machined at both ends to mesh with the constant velocity (CV) joints.

Replacing them in the 2010 car were shafts comprising end pieces with integral spines made from laser sintered EOS Titanium Ti64 alloy.

They secured two ends of a 30mm-diameter, filament-wound, carbon-fibre tubular shaft supplied by Crompton Technology.

EOS Inconel 718 powder was laser sintered to produce the exhaust header, which is the first stage in the exhaust system and has to withstand high temperatures and vibration.

The Inconel header has a section thickness that varies from 0.5 to 5.0mm due to the application of Hyperworks modelling, analysis and simulation software from Altair Engineering.

It allowed the volume of material in the header to be reduced, cutting the weight 40 per cent while maintaining performance.

It is difficult to optimise the shape and length of the car’s induction system early in a Formula Student project, so it is advantageous to leave finalising the design until the last minute.

For the university’s entry last year, the plenum chamber and inlet runners were produced quickly from alumide powder in WMG’s Eosint P 380.

Layer-by-layer manufacture from the CAD model gave design flexibility while the polyamide and aluminium mixture produced a stiff structure.

Little post processing was needed and the component only needed porosity sealing and painting.

Weight was cut to under 1kg, significantly lighter than the cast and fabricated induction systems used in previous years.

Other components on the car, especially late-configurable items, were designed on the fly and made from alumide to reduce weight.

They included boxes for the electrics, cable clips, dashboard panelling and the rear light brackets.

Smaller parts such as the clips were made inside the void of the plenum chamber to maximise use of the P 380’s build volume.

Not only do the Formula Student judges assess each car’s speed, manoeuvrability and endurance, but they also appraise cost, business potential and aesthetics.

In the latter respect AM has a big contribution to make, as it does not matter how complex a part is – it will be just as easy to manufacture as a simple one – so the degree of design freedom is almost limitless.

Similarly, it is immaterial if each clip is slightly different from the next, as there is no penalty in manufacturing cost or time.

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