Increasing of anodic oxidation quality of twin rool caste 1050 type aluminum sheets

ABSTRACTAnodization of aluminum sheets which is produced by twin roll casting process werestudied. The surface quality of sheets that is accepted in the market from direct chillcasting process was intended.Both ordinary and improved TRC sheets in order to increase the surface quality bychanging some casting parameters were taken. Tests were carried out with design ofexperiment (DOE) in etching bath. Only the etching bath concentration, temperature andtreatment period were changed, but other degreasing, deoxidation, anodization, rinsingparameters were held constant.Brightness, color difference, roughness properties of anodization layer after DOE inetching operations were measured.Anodization layer structure on TRC sheet is very different in these tests with existentpretreatment and anodization parameters when compared with DC sheet. Scanningelectron microscope have shown the difference of cell and pore dimensions, also thepopulation.Metal composition, microstructure and anodization bath parameters have respectedinfluence on cell and pore dimensions. But this study have focused on etching bathparameters in order to increase the TRC sheet quality before anodization operations aswell.A few more trials needed to obtain required surface for anodization with TRC sheetsalso by improving casting parameters or changing anodization parameters to liken DCsheets that were prepared after casting with different technique and scalping operations.Keywords: Anodization, TRC, SEM, DOEI