Structural Characteristics and Properties of Zinc Coatings on Steel Structural Elements

Area of Science:

• Materials Science
• Surface Engineering
• Corrosion Science

Background:

• Hot-dip galvanizing is crucial for protecting steel structures like S235JR.
• Understanding zinc coating behavior on complex geometries is vital for industrial applications.
• Characterizing coating phases and properties informs durability assessments.

Purpose of the Study:

• To structurally characterize zinc coatings on S235JR steel elements.
• To assess coatings formed under industrial hot-dip galvanizing conditions on profiled steel.
• To provide practical insights into coating behavior on complex geometries.

Main Methods:

• Metallographic analysis to observe coating layers (η, ζ, δ, Γ phases).
• Mechanical testing for microhardness assessment.
• Diffraction and tribological tests for comprehensive characterization.

Main Results:

• Zinc coatings exhibit a layered structure with distinct phases (η, ζ, δ, Γ).
• Phases vary in chemical composition and microhardness.
• Thicker coatings on complex geometries demonstrated earlier adhesive crack formation and faster damage progression, despite similar initial damage resistance.

Conclusions:

• The layered structure and phase composition influence zinc coating performance.
• Coating thickness and substrate geometry significantly affect stress concentration and damage initiation.
• Findings offer practical insights for optimizing hot-dip galvanizing processes for complex steel elements.