Galvanized sheet quality defects and precautions

 Common quality defects of galvanized sheets
1. Defect name: Galvanizing peeling Defect manifestation: Dezincification Cause: poor furnace temperature, improper substrate handling, etc.
2. Defect name: Not galvanized Defect manifestation: The surface part of the steel plate is not galvanized Causes: Poor raw materials, poor pre-treatment degreasing, poor furnace temperature
3. Defect name: Poor zinc splatter. Defect manifestation: uneven splinter size, no splinter. Cause: poor heating in the furnace area and poor cooling control.
4. Defect name: Zinc scar Defect manifestation: Dotted and granular zinc slag adheres to the surface of the steel plate Cause: scum or bottom slag adheres to the steel belt in the zinc pot
5. Defect name: Oxidation defect manifestation: White rust occurs Cause: During storage, moisture in the air is absorbed and oxidized 2Zn+O2 → 2ZnO5ZnO+2CO2+3H2O →2ZnCO3·3Zn(OH)2
6. Defect name: black spots. Defect manifestation: black dots and lumpy spots. Cause: Impurities precipitate and react with moisture and carbon dioxide in the atmosphere, or are caused by friction during transportation.
7. Defect name: edge wave, middle wave Defect manifestation: wavy edge or middle part Cause of occurrence: poor raw material or poor working condition of the tension and straightening roller
8. Defect name: Jagged edge Defect manifestation: The edge is in a jagged shape Cause: The edges are uneven and jagged when the raw material is cold-rolled
9. Defect name: uneven board surface Defect manifestation: dent Cause: ridges or depressions caused by pits in the raw material or foreign matter adhering to the surface of the roller. GNEE STEEL offers a wide range of galvanized metal sheets.  GNEE STEEL is a leading galvanized metal supplier, providing high quality, low price galvanized sheet products to the global public.Seize the opportunity and contact us now to place an order!