Effects of artificial aging heat treatment on mechanical properties and corrosion behaviour of AA6XXX aluminium alloys

Abstract

In this study, the effects of artificial aging heat treatment on mechanical properties and corrosion behaviour of AA6XXX alloy were investigated. The effects of artificial aging time on microstructure and mechanical properties of alloy were analysed and at the same time corrosion behaviour was determined by corrosion tests. For experimental investigations, the alloy samples prepared in appropriate sizes were heated to 540°C (±0.5°C) with heating rate 10°C/min. by electrical resistance ceramic furnace. For the solution heat treatment, samples were kept in the furnace at this temperature for 4 h. The samples taken from the furnace were firstly poured into iced water at 10°C and then subjected to artificial aging at 190°C for 2, 4, 6, 10, 12 and 24 h. Finally, the samples taken from the furnace were left to cool down in stagnant air. The results show that the mechanical properties of the material were increased with increasing aging time. Corrosion tests have shown that the corrosion resistance of the alloy depends on the artificial aging time. The best value of corrosion resistance was obtained at a temperature of 190°C at 10-h aging period.

Effect of quenching treatment on corrosion behavior and mechanical properties of 6061 aluminum alloy

“…By using potentiostat device conferring to the ASTM (G-5) Standard , an electrochemical corrosion measuring was applied. By using the following equation the corrosion rate (C.R) can be calculated [1,11,12,13]: (1) Where: mpy: mils penetration per year. icorr: corrosion current intensity (A/cm 2 ).…”

“…Aluminum is the second most widely used metal in industrial applications in the world. The 6XXX series alloys denoted as is heat treatable, medium-strength alloys, moderate corrosion resistance, and excellent formability characteristics [1]. The 6061 alloys are used in general works (structure, handling instruments) and also for frameworks assembled by welding processes [2].…”

“…The 6061 alloys are used in general works (structure, handling instruments) and also for frameworks assembled by welding processes [2]. Magnesium (Mg) and silicon (Si) can produce various degrees of properties (such as strength) of alloys by heat-treated precipitation of the main solutes [1,3]. In other words, the strength of the 6XXX series can be greatly increased by performing two or more stages of heat treatment.…”

“…The 6XXX series alloys is including T6 temper that includes, solution treatment and follows with artificial aging treatment. The quenching treatment is a good method to improve some mechanical properties such as the strength of the alloy [1,4]. In general, the success of the cooling process depends mainly on the possibility of heat transfer to the cooling medium in order to obtain, a supersaturated solid solution.…”

“…Therefore, Quenching hardening is the most common method of use as heat treatment in the manufacturing industry, which leads to increased service reliability of the metal alloy components. Heating to about 175°C (for 6000-alloys in general between 160-200°C, will produce ''agehardening'', ''Artificial aging'' or simply ''aging'' [1] leads to precipitation of various phases at various amounts of time [3]. Based on that, when the alloys are exposed to a solution heat treatment followed up by quenching treatment and tempering, their mechanical properties up to their highest grade.…”