Abstract
The strength of adhesion on aluminum plate treated by phosphoric acid is compared with respect to the following two different methods of treatment; by one method the phosphor compound remains on the surface of aluminum plate and by the other it does not.
The result: On 12% Si-Al-alloy plate, both methods of phosphoric acid treatment are equally effective for the stronger adhesion, but on 2S, 56S, and 10% Mg-Al-alloy plates the former treatment is more effective than the latter.
The effect of the amount of silicon in aluminum alloys on the adhesion of paint is also studied. For the favorable adhesion the aluminum alloy should contain more than the critical 4% of silicon in case of the former treatment, and more than the critical 7% of silicon in case of the latter.
1) The author: Study on the Phosphoric Acid Treatment for Aluminum Plates; The J. of the Metal Finishing Society of Japan Vol. 5, No. 2, April 1954.
