LE MANS RADICAL AHEAD WITH INNOVATIVE USE OF CERAMICS Plasma-sprayed ceramics are helping the Rollcentre team reduce weight and increase the durability and efficiency of its LMP2 Le Mans entry When the Radical marque makes its debut at this...
LE MANS RADICAL AHEAD WITH INNOVATIVE USE OF CERAMICS
Plasma-sprayed ceramics are helping the Rollcentre team reduce weight and increase the durability and efficiency of its LMP2 Le Mans entry
When the Radical marque makes its debut at this year's Le Mans 24-hour race, it will be with a car that uses technology developed by the nuclear industry to make it lighter, more durable and more efficient. Prepared by Rollcentre Racing, the LMP2 (prototype class) car will use zirconia ceramic coatings plasma-sprayed onto carbon composite panels as well as in the more conventional application of exhaust system coating.
Rollcentre boss Martin Short had already used the Zircotec coating on the exhaust systems of a pair of Dallara-Judd V10 sports cars previously run by his team and had been impressed. "Engine bay temperatures were reduced and we did not have a single exhaust manifold problem," he says. The advanced coating, already relied upon by five Formula One teams, helps to retain heat within the exhaust system, increasing engine power and protecting the bodywork and local components from extreme exhaust temperatures.
For two years, Rollcentre Racing entered its Dallaras in a series of long distance races including the ultimate test of a racing car, the Le Mans 24-hours, where the team performed with great credit. This season, Rollcentre has become the first team to enter Le Mans with a sports prototype manufactured by Radical, the fast growing British racing car manufacturer. In the preparation of the car, Short's team has again turned to Zircotec for assistance. "When you've got something good it is best to stay with it," he observes.
The Zircotec process, originally developed by the UK Atomic Energy Authority to help manage extreme temperatures in nuclear power stations, is being used in two ways on the Rollcentre Radical-Judd V8 SR9. As with the Dallaras, the 421 Inconel exhaust system, supplied by Good Fabrications, has been plasma-sprayed with a ceramic thermal barrier to reduce thermal radiation. Due to LMP2 regulations the system is largely confined within the A frame, so heat build up could damage the local components and body panels and increase intake air temperature, which would reduce engine efficiency. The Zircotec coating manages all of these issues.
A second challenge is that the hot exhaust gasses are released from the pipes in a recessed area of the bodywork at the rear. The simple answer to this, used by the team in the season's first race, is to use heat-resistant stainless steel panels where the problem is most critical. However, carbon panels are much lighter, indeed can be up to a quarter the weight of their stainless steel equivalents. They are also much easier to fabricate. Without a suitable coating their use would, however, be impractical in this harsh environment.
Which is why Rollcentre, impressed by the effective of the Zircotec coating on its exhausts, has switched to carbon panels plasma-sprayed by Zircotec using a process specifically designed for this type of application. The process is generically similar to that for exhausts, but the surface preparation is modified to prevent damage to the carbon fibre matrix. The ceramic coated panels were first used by the team at the Spa 1,000kms race in May and now face their sternest challenge at Le Mans. At the Le Mans test weekend, the Radical was second fastest in its class.
THE ZIRCOTEC PROCESS
Originally developed by the nuclear industry, Zircotec's high temperature plasma-sprayed ceramic coatings provide lightweight, easily packaged and highly durable thermal barriers for a wide range of highly aggressive environments including motorsport. A major reason for its use in this sector is to protect surrounding structures. Carbon fibre body parts, if scorched, can delaminate. It is also important to stop heat ingress into lubrication areas such as gearboxes and oil supply and radiator lines and to ensure that air intake temperatures are as low as possible to increase charge density. Drivers are also able to concentrate more effectively if they are working in a cooler environment.
Zircotec's zirconia-based ceramics have a thermal efficiency of less than 1.7 W/m K, providing an excellent thermal barrier. When applied to an exhaust system, the Zircotec coating inhibits the radiation of heat from the surface of the material, holding the heat inside. The carbon coating uses a similar process to help protect the substrate material from heat sources in close proximity. www.zircotec.com