In the UK, the aerospace sector has been recognised as a key part of the country's manufacturing base and has been identified for government support through the Aerospace Technology Institute (ATI), which will deploy £2 billion over the next seven years to improve efficiency and environmental performance.
The aerospace sector is driven by the demand for materials innovation to improve aeroplane fuel economy. The use of lighter, stronger airframe materials as well as applying coatings to reduce drag can deliver significant fuel savings.
Currently chromium and cadmium are widely used in the automotive and aerospace industries as corrosion-resistant coatings. However, the EU has banned their use as part of its Restriction of Hazardous Substances Directive and aerospace companies are seeking alternative materials with the same innovative characteristics.
Ilika has been collaborating with a number of aerospace companies to develop new innovative materials to improve efficiency and environmental performance within this sector.
Using the Ilika High Throughput Physical Vapour Deposition (HT-PVD) platform, the company has developed methods to make and screen coatings in high throughput mode, allowing companies to identify alloys that can be potential candidates to replace existing materials.
Ilika adapted its high throughput screening methodology to employ multi-channel current followers and a silicon micro-fabricated array of independently addressable electrodes to the screening of corrosion characteristics of thin film materials. The screening methodology is compatible with the high-throughput PVD methodology allowing the controllable deposition of compositional gradients of a large range of thin film materials.
The method was applied to the study of a library of Ni–Cr alloys in order to assess the effectiveness of this high-throughput approach and an optical screening method was also used to assess corrosion behaviour of a library of thin films by image analysis of electrodes before and after exposure to the corrosion environment.
Further scientific details of the high throughput methods used to assess corrosion resistance are available in Electrochimica Acta 76 (2012) pp 389-393, which is available to subscribers at: http://www.sciencedirect.com/science/article/pii/S0013468612008110