corrosion
Electrochemical analysis of
Metrohm’s electrochemical corrosion analysis workflows deliver the insights you need in minutes or hours instead of weeks or months.
From corrosion-rate measurement to inhibitor evaluation and impedance modelling, our systems provide rapid, quantitative, and mechanistic understanding of corrosion phenomena. With techniques such as linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS), electrochemical noise (ECN), and polarisation (Tafel) analysis, you can probe both uniform and localised corrosion behavior with speed and precision.
Unlike traditional gravimetric or coupon-based testing that require long waiting times, these approaches enable in-situ, accelerated, and detailed study of corrosion pathways. Helping you make faster, better-informed decisions.
Why Electrochemical methods for corrosion?
Corrosion is fundamentally an electrochemical process: metals dissolve (anodic reaction) while electrons are consumed or shuttled by reduction reactions (cathodic). Electrochemical techniques allow you to interrogate these half-reactions in real time, offering access to corrosion currents, reaction kinetics, and charge-transfer resistances, information that gravimetric techniques cannot reliably provide, especially for localised phenomena like pitting or crevice attack.
Furthermore, electrochemical methods enable accelerated testing, replication, and mechanistic deconvolution of corrosion inhibitors, environmental effects, and protective coatings.
Types of corrosion
Uniform corrosion — relatively even metal loss over a surface; straightforward to quantify.
Pitting corrosion — highly localised, small cavities or “pits” that may penetrate deeply; often the most dangerous.
Crevice corrosion — occurs in shielded or stagnant microenvironments (e.g. under gaskets, sealing surfaces).
Galvanic corrosion — arises when dissimilar metals are connected electrically, causing the more active metal to corrode faster.
Microbiologically Induced Corrosion — driven or accelerated by microbial activity or metabolic by-products.
Key electrochemical methods & applications
- Linear Sweep / Tafel / Polarisation
Sweep potential to reveal anodic and cathodic behaviour. From the slope near Ecorr, extract Rp and corrosion current density. Ideal for quantifying corrosion rates, alloy comparison, and inhibitor screening. - Electrochemical Impedance Spectroscopy (EIS)
Apply small AC signals across frequencies to probe charge transfer, capacitance, and diffusion. Nyquist plots and equivalent circuit models provide insight into coatings, passive films, and interfacial processes. - Electrochemical Noise (ECN)
Measure spontaneous current and potential fluctuations at open circuit. A non-destructive tool for detecting localised corrosion such as pitting. - Long-Term & Cyclic Methods
Cycle polarisation or holds under changing environments to monitor impedance, Rp, or noise over time - tracking degradation, film breakdown, or inhibitor performance.
Applications & use cases
- Alloy screening: compare corrosion performance of material candidates (e.g. stainless steels, alloys, coatings) under various environments.
- Corrosion inhibitor evaluation: quantitatively assess inhibitor efficiency, mechanistic pathways (adsorption, film formation, blocking), and longevity.
- Coating and passive film evaluation: assess barrier properties, defect detection, and breakdown behavior.
- Environmental effect studies: examine influence of pH, chloride concentration, temperature, aeration, or contaminant species.
- Accelerated aging & cyclic durability: Get results in hours instead of months. Simulate harsh operating conditions with electrochemical stress cycles and monitor degradation.
Why Metrohm for electrochemical corrosion analysis?
- Proven instrumentation & integration
Metrohm offers robust potentiostats and impedance analysers like the µStat-i 400s and the FRA32M.S EIS Module, all fully compatible with NOVA and DropView software for streamlined experiment control and modelling. - Expertise & support
Backed by Metrohm’s global application specialists, training, and validated corrosion protocols. - Flexibility & scaling
From single-channel research with the µStat-i 400s to parallel testing with the µStat-i MultiX or µStat-i MXONE, Metrohm systems adapt to your unique needs. - Comprehensive ecosystem
Seamless links to equivalent circuit libraries, reporting tools, and other analytical techniques (e.g. titration, ion analysis) deliver a complete corrosion analysis platform.
VIONIC – Metrohm’s next-generation potentiostat/galvanostat
VIONIC powered by INTELLO integrates high performance and versatility in one instrument. Among its key features:
- ±50 V compliance, ±6 A current capability
- EIS up to 10 MHz
- Selectable floating mode
- Analog scan
- A second sense (S2) channel to monitor the counter electrode potential.
Because of its advanced specifications, VIONIC is particularly well suited for demanding corrosion studies involving wide potential windows, fast kinetics, or multi-electrode configurations.