Effect of surface roughness of electroplating chromium coated steel on bonding strength of polymer coated steel

The effect of surface roughness of electroplating chromium coated steel on bonding strength of polymer coated steel has been investigated in this paper. The experimental results have shown that the electroplating chromium coated steel with different surface roughness could be obtained through the substrate surface treatment before the electroplating process. The peeling test results have shown that the peeling force of the polymer coated steel would increase with the increase of surface roughness of the electroplating chromium coated steel, but the increase rate would become slow gradually. With the increase of surface roughness of electroplating chromium coated steel, the PET film would be damaged locally and some polymer residues would remain on the electroplating chromium coated steel; when the bonding force is large enough, the plating shedding would occur on the electroplating chromium coated steel. With the appearance of the polymer residues and the occurrence of plating shedding, the failure mode of polymer coated steel would transform from adhesion failure mode to the mixed failure mode.