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Definition: Corrosion engineering covers the holistic planning, assessment and optimisation of corrosion-relevant aspects in technical installations and products. It integrates material selection, protection concepts, operating parameters and inspection strategies. The aim is to sustainably ensure integrity and cost-effectiveness.

Practical relevance: The basis is knowledge of corrosion mechanisms, media conditions, temperature and pressure ranges as well as normative requirements (e.g. DIN EN ISO 8044, API 571). Measures include suitable material selection, coating systems, cathodic protection, water chemistry control and Risk-Based Inspection (RBI). A lack of systematic planning leads to increased maintenance costs and failure risks.

Decision-making perspectives:

• Technical decision-makers: Development of integrative corrosion protection strategies across the entire life cycle.
• Purchasing/project management: Definition of clear material and protection requirements in specifications.
• Science: Modelling of corrosion rates and assessment of new protection technologies.
• Insurance/law: Demonstration of systematic risk assessment and compliance with technical codes and standards.

Typical testing or verification methods: Corrosion testing, electrochemical analyses, wall thickness measurement (UT), RBI analyses, materials analytics.

FAQ:

• What distinguishes corrosion engineering from individual tests?
• It considers corrosion risks holistically and with a life-cycle orientation rather than as isolated individual tests.

Definition: Corrosion mechanisms describe the physico-chemical processes that lead to the degradation of a material through reaction with its environment. They are usually based on electrochemical redox reactions between metal, electrolyte and oxidising agent. The type and progression depend on the material, medium, temperature and mechanical loading.

Practical relevance: The most important mechanisms include uniform surface corrosion, pitting corrosion, crevice corrosion, galvanic corrosion, stress corrosion cracking (SCC) and hydrogen-induced cracking. Evaluation parameters are the corrosion rate (mm/year), potential differences, pH value and chloride content. Normative definitions can be found, among others, in DIN EN ISO 8044. Knowledge of the mechanism is a prerequisite for effective corrosion protection.

Decision-making perspectives:

• Technical decision-makers: Selection of suitable materials, coatings or protection systems.
• Purchasing/project management: Specification of corrosion-resistant materials and testing requirements.
• Science: Analysis of electrochemical processes and material-medium interactions.
• Insurance/law: Determining the cause of corrosion damage and assessing the duty of care.

Typical testing or verification methods: Electrochemical measurements, salt spray test, metallography, wall thickness measurement (UT).

FAQ:

• Why is identifying the corrosion mechanism important?
• Only by knowing the mechanism can suitable protection and prevention measures be defined.

Definition: Corrosion protection encompasses all technical measures to prevent or slow down corrosion of materials. It can be achieved through design, materials engineering, electrochemical means or coating systems. The aim is to extend service life and ensure operational safety.

Practical relevance: Measures include suitable material selection, coating systems in accordance with DIN EN ISO 12944, cathodic corrosion protection or adjustment of the water chemistry. Protection duration, coating thickness, adhesion strength and inspection intervals are assessed. The effectiveness depends strongly on environmental conditions such as humidity, chloride content and temperature.

Decision-making perspectives:

• Technical decision-makers: Selection of economically and technically suitable protection concepts.
• Purchasing/project management: Specification of protection classes, coating systems and testing requirements.
• Science: Investigation of passivation, diffusion processes and protection mechanisms.
• Insurance/law: Demonstration of appropriate protective measures in the event of corrosion damage.

Typical testing or verification methods: Salt spray test, coating thickness measurement, pull-off adhesion test, potential measurement in cathodic protection.

FAQ:

• Which standard governs coating systems in corrosion protection?
• DIN EN ISO 12944 describes the corrosion protection of steel structures by means of coating systems.

Definition: Corrosion testing is the experimental investigation of the resistance of a material or coating system to corrosive media. The aim is the quantitative or qualitative assessment of corrosion behaviour under defined conditions. Test methods are governed by standards, for example in DIN EN ISO 9227.

Practical relevance: Corrosion tests include salt spray tests, climatic tests, immersion tests or electrochemical measurements. The corrosion rate, mass loss, pitting corrosion or undercutting of coatings are assessed. The results serve material selection, qualification of coatings and service life estimation.

Decision-making perspectives:

• Technical decision-makers: Selection of suitable material or coating systems for defined media.
• Purchasing/project management: Definition of binding test requirements and acceptance criteria.
• Science: Investigation of corrosion kinetics and comparison of accelerated test methods with field exposure.
• Insurance/law: Demonstration of resistance or root cause determination in the event of corrosion damage.

Typical testing or verification methods: Salt spray test (DIN EN ISO 9227), condensation cyclic climate, electrochemical polarisation measurement, long-term exposure.

FAQ:

• Does the salt spray test replace real operating conditions?
• No, it is an accelerated comparative method and reflects real operating conditions only to a limited extent.