Questions and Answers | Latest
Version | 2025/2026 | Correct & Verified
What is the primary purpose of corrosion prevention in industrial settings?
✔✔To protect metal assets from deterioration and extend their service life.
Which metal is most susceptible to rust when exposed to moisture and oxygen?
✔✔Carbon steel.
What is the main factor that drives electrochemical corrosion?
✔✔Presence of an electrolyte, metal, and oxygen or another oxidizing agent.
Which component in a corrosion cell acts as the anode?
✔✔The metal area that loses electrons and corrodes.
Which component in a corrosion cell acts as the cathode?
✔✔The metal area that gains electrons and is protected.
Why is moisture critical in the corrosion process?
✔✔It acts as an electrolyte allowing electron flow between anode and cathode.
Which type of corrosion occurs uniformly across a metal surface?
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,✔✔Uniform corrosion.
Which type of corrosion results in deep localized pits?
✔✔Pitting corrosion.
What is galvanic corrosion?
✔✔Corrosion that occurs when two dissimilar metals are electrically connected in an electrolyte.
Why is proper surface preparation important before coating?
✔✔To ensure adhesion, performance, and long-term corrosion protection.
Which tool is commonly used to remove rust and mill scale before coating?
✔✔Abrasive blasting equipment.
What is the primary purpose of a primer in a coating system?
✔✔To promote adhesion and provide corrosion protection.
Which coating property prevents moisture from reaching the metal surface?
✔✔Barrier properties.
Why is monitoring ambient temperature important during coating application?
✔✔Because temperature affects curing and adhesion.
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, Which factor increases the risk of underfilm corrosion?
✔✔Trapped moisture or contaminants under the coating.
What is flash rust?
✔✔Rapid formation of rust on a freshly prepared steel surface before coating.
Why is it important to monitor relative humidity during coating application?
✔✔High humidity can cause condensation and interfere with coating adhesion.
Which surface profile is ideal for most industrial coatings?
✔✔A roughened surface with peaks and valleys for better mechanical adhesion.
Why should coating thickness be measured after application?
✔✔To ensure compliance with specifications and proper protection.
Which instrument is used to measure dry film thickness on steel?
✔✔Magnetic pull-off or electronic thickness gauge.
What is the purpose of a holiday test?
✔✔To detect discontinuities or pinholes in coatings.
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