LEIS470 Localised Electrochemical Impedance System

Monitors and maps the local impedance of a sample in solution

The LEIS470-3300 allows spatially resolved impedance measurements to be made, combining established principles of EIS measurements with Uniscan?s unique Model 470 scanning probe technology and has been designed to provide a totally integrated spatially resolved measurement system.

The principles of LEIS are similar to those employed in traditional bulk EIS, in that a small sinusoidal voltage perturbation is applied to a working electrode sample and the resulting current is measured to allow the calculation of the impedance. However, rather than measure the bulk current, a small electrochemical probe is scanned close to the surface, measuring the local current in the electrolyte.

Producing area maps over a sample at a single frequency has never been easier. The LEIS470 also allows the user to make galvanic or bulk impedance measurements simply by choosing which mode the potentiostat is operating in, and the software does the rest.

Materials

• Plastic deformation and microstructures of Ti-6Al-4V
• Ageing and shock processing on AA2050-T8 aluminium alloy

Fundamentals

• Scanning photo-induced impedance microscopy
• Assessing electrochemical microcell geometry

Corrosion

• Delaminated areas beneath organic coating
• SMART protection of water based epoxy coatings
• Single pit initiation on 316L stainless steel
• Localised corrosion of steel in oilfield formation water