The determination of optimum conditions for anodizing aluminum alloy (6063)‎

Abstract EN

Aluminum alloy (6063) has been anodized using sulfuric acid as an electrolyte.

To study the characteristic of the anodic film, four variables, were considered as the most dominant variables.

These variables are : current density in the range of 1- 4 A / dm2, electrolyte concentration in the range of 6-20 vol.%, electrolyte temperature in the range of 10-30oC and anodizing time between 12- 60 min.

These four variables are manipulated through the experimental work using Box_ Wilson experimental design where second order polynomial model was proposed to correlate the studied variables with the thickness of anodic film of aluminum alloy (6063) to estimate the coefficients of the proposed polynomial adopted via statistic software.

The predicated models are found after statistically analyzing the significance as follows : Y= 27.7800 + 8.0737X1 - 0.8037X3 + 8.2078X4 - 0.6994X21 - 0.8882X22 - 1.5582X23 -1.1231X1X2- + 2.6225X1X4 - 1.7931X2X3 - 1.6956X2X4 - 1.0581X3X4 Where Y is the objective function (thickness of anodic film), X1 is the current density; X2 is the electrolyte concentration ; X3 is the temperature of electrolyte and X4 is the anodizing time.

The study shows that the anodizing time and current density had shown positive dependence of great significance on the anodic film thickness while the other two studied variables (i.e.

concentration and temperature of electrolyte) had shown small dependence on the film thickness of aluminum alloy (6063).

Optimum conditions for achieving the maximum film thickness are obtained from optimizing the above correlation and are found as follow : 4 A / dm2 Current density, 6 vol.

%Acid concentration, 19.5 oC Electrolyte temperature and 60 min.

time of anodizing.