A lightweight aluminium foam could help to reduce the carbon emissions of the worldwide freight industry by cutting the weight of ships by up to 30 percent.
German-based Fraunhofer Labs has developed an aluminium-titanium hydride powder that foams when heated, rising like a loaf of bread. The powder — which is lighter than water — is pressed into blocks and then placed between two steel sheets before being heated in the oven.
When the temperature hits 649 degrees celsius, the foam rises and bonds to the steel to create large aluminium foam sandwich plates. These could eventually replace the steel plates conventionally used in large scale boat-building. The material is very tough, resisting breakage under pressure. This could allow for ships that could travel through the icy waters of northern Europe.
Modern cargo ships that can travel through icy waters tend to weigh 770 – 900 tonnes and carry a further 2,700 tonnes of cargo. An EU project aims to reduce the weight of the vessel down to 450 tonnes, but maintain a cargo capability of 2,600 tonnes. Fraunhofer Labs’ metal foam could cut ships’ weight by 30%. If combined with plastic composites, the weight reduction could be considerably greater.
Fraunhofer Labs has also developed a medical implant grade titanium foam that could be used to repair damaged bones more effectively then the plates currently in use. The foam has a complex internal structure that allows blood vessels and existing bone cells to grow into the foam.