Corrosion analysis: identify the source and validate your materials

Corrosion observed on a part, coating, or assembly can lead to production stoppages, non-conformities, performance losses, and quality disputes. A rigorous corrosion analysis makes it possible to identify the attack mechanism, trace back to the corrosion origin, and determine whether the failure comes from the material, the surface treatment, the exposure environment, or the manufacturing process. This approach is intended for manufacturers in every sector looking to improve the reliability of their equipment, compare several material solutions, and document technical expertise that can be used in production as well as in R&D. To broaden the approach according to your field, consult our dedicated pages by industry sector and our expertise in materials laboratory.

Expert analysis relies on a cross-reading of morphology, chemical composition, and microstructure. Observations using electron and optical microscopy highlight surface defects, deposits, cracks, wear, irregularities, and initiation zones. Chemical and elemental analysis verify the metal grade, look for oxidizing or corrosive agents, and confirm the nature of contaminants present at trace levels. Micrographic cross-sections are particularly useful for checking the integrity of a deposit, the condition of the substrate, and the depth of attack; on this topic, also see metallographic cross-sections.

The technical methods available include SEM-EDX and FEG-SEM to observe the morphology and composition of surfaces and deposits, optical microscopy for metallographic observations, ICP-AES for trace element detection, XPS for surface chemistry, XRD for identifying crystalline structures, as well as hardness measurements and C/S, N/O, H elemental analysis. Together, these methods make it possible to verify the compliance of a grade, detect precursors such as halogens or contamination, assess the degree of oxidation, and characterize the actual condition of a failed part.

Calling on an expert laboratory means obtaining a well-supported diagnosis, targeted tests, and directly actionable recommendations. The approach covers failure analysis, material compliance checks, coating evaluation, comparative studies, and pre-industrialization validation. It helps reduce the risk of recurrence, guide material selection, improve specification sheets, and enhance the durability of parts in service.

Before industrialization, during qualification, or as part of quality monitoring, it is essential to validate materials and processes against real or simulated environments. The goal is to measure corrosion resistance, assess the uniformity of a surface treatment, check coating thickness loss, and anticipate degradation mechanisms. Electrochemical tests, accelerated aging, and surface analysis make it possible to compare metal grades, paints, deposits, or anticorrosion protections in specific environments: chlorides, seawater, extreme pH, or inhibitive media. To explore further the links between material behavior and performance, also discover our content on materials science.

When corrosion is accompanied by fracture, fractographic analysis makes it possible to characterize the fracture surface and identify the mechanisms involved: brittle, ductile, fatigue, or stress corrosion cracking, depending on the clues observed. Comparing sound and failed areas by hardness, microstructure, and composition helps confirm the sequence of causes. This expertise makes it possible to rank contributing factors and propose concrete corrective actions on material selection, surface treatment, assembly, or service conditions.

To validate materials and processes, electrochemical tests provide robust comparative data: measurement of the open-circuit potential OCV to assess the spontaneous behavior of a metal, determination of corrosion rate by LSV, measurement of electrochemical impedance EIS to detect defects in protective coatings and study their uniformity, and study of galvanic coupling to analyze interactions between two metallic materials. These tests can be supplemented by salt spray exposure, accelerated aging, and simulations of specific environments such as seawater, acidic, alkaline, chlorinated, or inhibitive solutions.

Support can include the design of corrosion test plans, simulations of specific environments, materials/process quality monitoring, as well as R&D support to develop more durable solutions. The results are useful for investigating a non-conformity, justifying a supplier change, qualifying a new surface treatment, or documenting technical decision-making in a demanding industrial context.

A corrosion analysis should be initiated as soon as signs of abnormal oxidation, pitting, deposits, cracks, thickness loss, coating delamination, or unexplained failures appear. It is also relevant upstream to qualify a new material, compare several anti-corrosion protections, secure a process change, or reproduce a harsh environment before market launch. To move forward effectively: identify critical areas, characterize deposits and surfaces, compare materials and coatings, simulate the operating environment, validate the most robust solution.