New tech to raise composites quality and slash costs

Posted on 19 Dec 2012

A new composite technology that heats and cools different sections, reducing residual stress and slashing energy use by 75%, has been created by a British company.

Trials of Surface Generation’s curing process for carbon composite structures showed that it provided greater regional control than traditional autoclave and oven curing, as well as being much more energy efficient.

Ben Halford, chief executive at Surface Generation said that the technology “represents the biggest step forward the industry has seen in years.”

Mr Halford, remarked that the trials “provide more evidence that the future of carbon composite processing lies outside of the oven and auto-clave.”

The trials conducted by materials company Cytec showed that tool-face temperature measurements were consistently within 0.5°C to 2°C of specified levels.

It localises energy input to suit the thickness of the component, which is not possible with autoclave and oven cure processes that heat the entire space to a chosen temperature. This means that parts for the aerospace, defence and wind turbine market will be stronger and less susceptible to cracks.

Taking the wind turbine as an example, it has a thick area at the root and thin area at the tip, yet they are treated by one heating process.

As with cooking food, thinner parts of the wind turbine requires less heat, so the process heats each square of to the different levels required.

The project, which began four years ago and was developed in house at the company’s site in Rutland, near Leicester, looked at what the market was doing and realised there were some big gaps in there and developed technology to address that.

“Some people are living with some very high scrap rates,” says Halford. “The system works in a fundamentally different way to conventional processes whereby manufacturers cross their fingers until it comes out [of the autoclave or cooker]. Our system manages the local areas of the part during the cure and we can see what’s going on in realtime.”

After working on the technology following a requirement from the US military, Halford explains that the system has a pixelated view of control.

Comparing it to a chessboard, he says that “each square is individually heated and cooled independently of its neighbours so you can put more energy into thick areas and less on the thin ones.”

It divides the world up into squares, with separate heating and cooling circuits to treat different surface areas of a component so that there are no weak spots.

Six systems have been sold so far, with the company quadrupling staff levels last year to 17.

Surface Generation is actively recruiting again now and numbers could double again by the end of 2013. “Most installations will pay for itself within a year because of energy savings, alongside the potential rise in sales that could result from better quality,” commented Halford.

The company is selling to aerospace and automotive companies, as well as materials suppliers.

Halford believes that the bespoke heating technology could revolutionise consumer electronics after having developed a different version of same system with shorter, two minute cycle times to make a part.

“This is a 50% time saving compared to the best composite techniques in the marketplace,” said Halford. “If you can do that then people will move from using metal on laptops and phones to composites.”

Its systems are in place in the US, Germany, Switzerland and the UK and will be in Japan and Taiwan shortly.

Predicting £3m worth of sales in the next year, Halford remarks that the technology “has totally transformed the business.”

“We were very marginal start up before, but we are a new business with this technology. Four years ago we could have changed the name as far as the market was concerned,” he added.

The chief executive predicts that the company could sell 20,000 heating machines if it goes into high volume consumer electronics. Can it meet demand if it arrives? “Some of our backers have founded FTSE listed companies and they are industrials so we are prepared to go the full course [and not sell the company],” he said.

Alasdair Ryder, manufacturing manager at material group Cytec, which tested the system, commented: “The combination of out-of-autoclave technologies has significant potential to drive cost, quality and efficiency improvements in carbon fibre composite manufacturing processes.”