Corrosion and Material Degradation Testing

In-situ and laboratory corrosion and material degradation testing services

Dr Tamsin Dobson

Applied Marine Scientist - Biocorrosion Lead

PML Applications supports clients by assessing corrosion and material degradation using field-based and laboratory-based testing, providing failure analysis and assisting with material selection and protective coatings. Find out more about our independent corrosion testing services.

Our bespoke services consider corrosion and material degradation holistically, including the interacting effects of biofouling and the specific operational context. Types of corrosion testing available include:

Lab-based corrosion testing: Electrochemical testing (OCP, EIS, etc.) using biologically inert, real seawater in a controlled environment (temperature, salinity, pH, seawater flow rate, etc.).
Field-based corrosion/biocorrosion testing: Corrosion testing (immersion testing) in the real-world marine environment using time-lapse methods in areas where the biological load is well characterised.
Material degradation testing for composites and plastics: Assessing composites and plastics using lab-based and/or field-based testing under real environmental conditions using standard or bespoke test rigs.
Corrosion surveys and consultations: In-person corrosion surveys of marine structures, vessels, and components by Security Cleared personnel.
Bespoke material screening: Bespoke experiments to test different materials in the conditions they would experience in service to aid in the down-selection of materials for new-design.

Standard and Bespoke Testing at PML Applications

In addition to testing to applicable British or ASTM standards, PML Applications develops bespoke corrosion testing methods to consider the specific material degradation issues within the relevant in-service contexts experienced by our clients. This includes trials and testing for:

Stress corrosion cracking (SCC)
Galvanic corrosion
Crevice corrosion
Microbiologically Influenced Corrosion (MIC)
Electrochemical corrosion testing
UV and chemical degradation
Mechanical degradation
Immersion test
Etc.

These types of corrosion tests can be conducted in a controlled laboratory environment to gain a detailed understanding of degradation mechanisms or, for field testing, in the real-world marine environment. Field tests have the advantage of including real-world variables for seawater physicochemical parameters (e.g. salinity, temperature, pH, dissolved oxygen, etc.), biological influences (e.g. biofouling and MIC), and weather and seawater dynamics (e.g. wave and tidal loading).

Lab-Based Corrosion Testing at PML Applications

PML Applications’ laboratory corrosion tests measure corrosion rates, severity, and mechanisms in real time or using time-lapse experimental methods.

We utilise a range of electrochemical techniques, including open circuit potential (OCP) monitoring, Electrochemical Impedance Spectroscopy (EIS) and Linear Polarisation Resistance (LPR), supported by the weight-loss technique and microscopic analysis.

In our specialised temperature-controllable marine testing laboratories, we use simulated seawater or locally sourced seawater that is made biologically inert, theoretically removing biofouling and biocorrosion as a variable. We set up your testing using precise conditions with monitoring and control of salinity, pH, dissolved oxygen, and seawater temperature. Our seawater flume is suitable for conducting corrosion tests to assess corrosion rates in variable flow conditions.

Controlled or monitored variables of the seawater flume include:

Temperature
pH / chemical immersion
Loading
Wear / tribocorrosion
Seawater flow rate
Erosion corrosion
The effect of different coatings
Etc.

Field-Based Corrosion and Biocorrosion Testing at PML Applications

Field-based corrosion and biocorrosion testing allows our clients to understand the corrosion performance of their materials, components, or assets when immersed in the real marine environment with its many time-dependent variables and unknowns.

We offer short-term or long-term immersion tests at a variety of locations using our standard or bespoke rigs, for example:

Short or long-term static immersion tests to consider the combined effect of biofouling and corrosion.
Short or long-term dynamic immersion tests, either to consider the effect of speed on corrosion or to investigate biofouling release.

Our deployment areas are fully biologically characterised and environmental data will be provided alongside any corrosion/biocorrosion and biofouling data.

Our rigs can be set up to test:

Biofouling effects (biocorrosion and/or MIC)
UV effects
Loading effects
Wear effects / tribocorrosion
The effect of different coatings
Etc.

Add electrochemical elements, final weight loss, and/or microscopic analysis as part of PML Applications’ bespoke corrosion testing services.

Material Degradation Testing for Composites and Plastics

Tailor your material degradation testing to be lab-based (e.g. for initial testing) or field-based, with a complete package available for robust material degradation assessments. Material degradation testing for composites and plastics tests for decomposition and material breakdown to predict durability, test environmental safety, or evaluate biodegradability.

To help you test under specific conditions, these tests for material degradation use controlled or monitored variables, including:

Temperature
pH / chemical immersion
Biofouling effects (monitored only)
UV
Loading
Wear
Seawater flow rate
Erosion corrosion
Etc.

Post-immersion testing options include:

Visual observations
Bending tests
Drop tests
Microscopic analysis
Etc.