The main difference is the alloy between the Galvanized steel sheet and Galvanized aluminum steel sheet, galvanized steel sheet covered a zinc layer evenly on the surface, it provide the anode      protection to the mother material, that is to say, the zinc sacrificed first instead of the mother material when in use,the mother material would hurt only after all the zinc vanished.

Galvanized aluminum steel sheet had alloy surface, the alloy content of 55% Aluminum and 43.5%    Zinc and a little of other element. In the microscopic view the surface of Al-Zn alloy is a      honeycomb structure, zinc surround by aluminum honeycomb. In this situation, even the galvanized aluminum alloy have the anode protect but the function of anode protection reduced tremendously.  That is because honeycomb structure and reduced rate of zinc, the zinc could not sacrificed so   fast. So if the galvanized aluminum steel sheet being cut, on the cutting edge almost lost the    protection,then it would rust rapidly on the cutting edge.By this reason the galvanized aluminum steel sheet better not cut,if have to cut the cutting surface should apply rustproof paint or zinc paint in order to made the product long using life.

The surface of galvanized aluminum steel sheet looking better than the galvanized steel sheet,    same the price of galvanized aluminum steel sheet higher than galvanized steel sheet. The zinc   shape small price higher than big zinc shape for the galvanized steel sheet.

In a city so much rain or in the air is humid,once a point on the galvanized aluminum steel sheet  appear rust if you don't take timely measures to the gradually corroded place, it will become    bigger and bigger finally spread to the whole board surface；but the galvanized steel sheet will not spread if it does.