principle and process description of hot galvanizing!
3. Formation process of hot galvanizing layerBack to the parentGalvanized layer formation process is the most out of pure iron substrate and formed between the zinc layer of iron, zinc alloy, the process of workpiece surface formed in hot dip plating of iron - zinc alloy layer, and makes good combination between iron and pure zinc layer, the process can be simply described as follows: when the blacksmith a immersed in molten zinc liquid, in the first place on the interface formation of zinc iron heart (body) with a solid solution. This is a crystal formed by a matrix metal iron in a solid state dissolved by zinc atoms. The two metal atoms are fused with each other. So when zinc in solid solution after reaching saturation, two kinds of zinc iron atom diffusion, spread to (or called infiltration) iron matrix of zinc atom in the lattice matrix, migration, gradually formed and iron alloy, and spread to molten zinc liquid iron and zinc in the formation of intermetallic compounds FeZn13, sank into the hot dip galvanized pot is zinc slag. When the workpiece is removed from the zinc immersion solution, a pure zinc layer is formed on the surface, which is a hexagon crystal. Its iron content should not exceed 0.003%.
4.Hot dip galvanizing process and related instructions
4.1 process!Workpiece 1 degreasing - washing - pickling - washing - washing - immersion plating solvent - drying preheating - hot galvanizing 1 finishing cooling - passivation - rinsing - drying - testing,
4.2 relevant process description
(1) skim,Can use chemical degreasing oil or water base metal degreasing detergent oil, until the workpiece is completely soaked by water.
(2) the pickling,