Protective coatings for mechanical aluminum–magnesium joints

Abstract

AZ31 alloy is used as a lightweight material for structural application in the automobile and aircraft production. However, alloy AZ31 is known to have poor corrosion resistant due to high electrochemical activity. In this study, the possibility of improving the corrosion resistance by applying protective coatings deposited by the low pressure cold spray process was investigated. The relative performance of each cold sprayed corrosion preventive coatings was assessed in accordance with American Society for Testing and Materials standards. The data for the bare AZ31 alloy were initially obtained and used as a reference point to compare the corrosion protective performance of different preventive coatings. Electrochemical behaviour of each coating composition was analyzed after a given time period of the accelerated corrosion test. Microstructure and mechanical properties of the deposited preventive coatings are also discussed. The cold sprayed preventive coatings provide sufficient protection to substantially reduce the corrosion rate of alloy AZ31.

A perspective review on the bonding mechanisms in cold gas dynamic spray

“…Therefore, it can cope with the production of different kind of coatings, pure metals, alloys, composites, nanostructure materials as well as amorphous materials [11][12][13], on a wide variety of substrate. The cold spray technique can be usefully used in many critical applications, such as biomaterials field, polymer and polycarbonates surfaces and marine environment [14][15][16][17]; functional coatings can also be manufactured by CS to improve the performances of the components to the operating conditions, in particular, fatigue [18,19], wear [20,21] and corrosion [22][23][24][25][26]. It was also proved to be an effective method to produce free shape precursors for metal foams structures [27,28].…”

Fabrication of icephobic aluminium surfaces by atmospheric plasma jet polymerisation

“…Due to its good formability, conductivity of heat and electricity and a high strength to weight ratio, aluminium (Al) and its alloys are widely used in diverse fields, including electronic, medical, automotive and aerospace industries [1][2][3]. However, ice accumulation on aluminium surfaces results in serious problems where these surfaces are exposed to harsh environmental conditions over long periods [4,5].…”

Coatings to increase the corrosion behaviour of aluminium foam

“…Salt spray test, at neutral or acidic pH, is the most used accelerated test to check the corrosion protection performances of coatings on aluminium and aluminium alloys. 5,23 For this reason, the corrosion resistance of the coated and bare foams is evaluated by acetic salt spray exposure test according to ASTM B117 24 and ASTM G85 25 for a total time of 1000 h.…”