Analysis of Technological Approaches to Electrochemical Surface Treatment of Aluminum Alloys

Abstract

Technological approaches to surface electrochemical treatment of aluminum alloys are analyzed. It is shown that directed modification of the carrier surface allows expanding the functional properties of the treated material. The mechanisms of treatment of aluminum alloys of different composition are investigated and technological models of processes using generalized phenomenological schemes are developed. Methods surface forming treatment of aluminum alloys by pulse current forming in chloride-containing electrolytes and plasma electrolytic oxidation in alkaline solutions of diphosphates are proposed. It is shown that the use of pulse electrolysis promotes the formation of a developed mesh and porous structure. Control methods and factors of the treatment process are generalized. The resulting systems can be used as carriers of catalytic material provided that a secondary catalytically active layer is applied. It is found that using plasma electrolytic oxidation, it is possible to change the shape and homogenize the surface layers of the carrier and apply a tightly adhered layer of catalytic material in one technological process. It is shown that the characteristic parameters of PEO depend on the composition of the treated material. It is revealed that the morphology and phase structure of surface oxide layers change during PEO. The formed oxide coatings consist of α-Al 2 O 3 and have a high degree of surface development, which is a prerequisite for increasing their functional properties. The proposed approach can be used in surface engineering technology and for obtaining materials for environmentally friendly technologies