Spray zinc, spray aluminum technology and similar performance comparison (hot-dip galvanizing process)
1, hot-dip galvanizing process
pretreatment using pickling, phosphating process, the surface of the workpiece will be acid, lye residue, leaving a hidden risk of corrosion, so that hot galvanized layer prone to fall off. Sprayed zinc, sprayed aluminum pretreatment using sandblasting process, so the workpiece surface is very clean and rough, the surface sprayed zinc, sprayed aluminum will not produce corrosion from the inside out, which will not produce zinc layer off phenomenon.
2, hot-dip galvanizing process has a certain temperature, about 440 ℃ or so, so the workpiece will be deformed after hot-dip; and spray zinc, spray aluminum spray when the temperature is very low, the workpiece surface temperature <80 ℃, so the workpiece is not deformed.
3, the use of hot-dip galvanizing process, the workpiece by the plating tank length × width × height limit; and the use of spray zinc, spray aluminum process is no restrictions on the workpiece.
4, the use of hot-dip galvanizing process, there are still on-site repair problems. Site installation of the weld, handling, transport process damage, repair can only use paint, resulting in a breakthrough process. Such as the use of spray zinc, spray aluminum process, the scene can be sprayed zinc, spray aluminum method to repair, to avoid a breakthrough process.
5, due to the hot-dip galvanizing process pretreatment using pickling, phosphating, so the workpiece surface without roughness, coating adhesion is poor. The spraying of zinc, spray aluminum pretreatment using sandblasting, Sa ≥ 2, so the workpiece surface roughness, coating adhesion is better. Tensile strength ≥ 0.6kg / mm2.
6, hot-dip galvanizing process of water pollution is very serious, environmental issues are very prominent. So hot spray zinc, spray aluminum technology in the more widely.