Q:Effect of galvanized steel surface on corrosion resistance?
A:Moderate roughness: Appropriate surface roughness can increase the mechanical engagement area between the coating and the substrate, improve the adhesion of the coating, and slow down the penetration of corrosive media (such as moisture and salt spray) into the substrate.
Too high roughness: "Corrosion traps" are easily formed in the deep pits or valleys of the surface. The residual acid, salts and other impurities are difficult to clean, which becomes the starting point of local corrosion (such as pitting).
The coating thickness on the rough surface is uneven (the coating is thin in the concave area and thick in the convex area). The thin coating area is easily corroded and penetrated first, causing the substrate to rust.
Roughness is too low: A surface that is too smooth will reduce the mechanical bonding between the coating and the substrate, making the coating easy to peel off and lose its protective effect.
Q:Effect of surface roughness of galvanized steel on mechanical properties?
A:Too high roughness: Surface peaks are prone to stress concentration during friction, leading to increased wear (such as bolt connections and gear meshing scenarios).
Too low roughness: Too smooth a surface may reduce the friction coefficient and affect the anti-slip performance between components (such as stair treads and anti-slip steel plates).
Q:What effect does galvanized steel surface roughness have on coating and paint adhesion?
A:Appropriate roughness can form an "anchor pattern" structure, enhance the mechanical bite of the coating (such as paint, powder coating) and the galvanized layer, and prevent the coating from peeling off.
Too low roughness (such as mirror polished surface) will lead to insufficient adhesion of the coating, easy to bubble and fall off; too high roughness may cause uneven coating thickness and poor surface flatness.
Q:What effect does the surface roughness of galvanized steel have on appearance quality?
A:Precision instrument casings, decorative components, etc. have strict requirements on surface roughness. Too high roughness will lead to reduced surface gloss and rough texture, affecting the appearance.
Q:What impact does surface roughness have on subsequent processing quality?
A:For galvanized parts that require subsequent processing such as welding, electroplating, and spraying, surface roughness will affect the processing quality.
For example: During welding, oil or oxides may remain on the rough surface, resulting in defects such as weld pores and cracks.
During electroplating, the coating on the rough surface is unevenly deposited, affecting the appearance and protective performance.