Optimizing the Heat Treatment Parameters of Al-6061 Required for Better Formability

Abstract

Aluminium alloys are widely used in several engineering applications due to their high strength-to-weight, ease of availability, comparatively low cost and ease of machinability. These alloys are classified into heat treatable and non-heat treatable, among which the former have more applications. Al 6061 is one among them that has relatively higher strength and good formability. There are several tempers of Al 6061 available ranging from T1 to T9. However, tempers T4 and T6 are the ones with better mechanical properties and are hence more widely used. Al 6061-T4 has better formability (percentage of elongation of 18.8%) but lower yield strength whereas Al 6061-T6 has lower formability (percentage of elongation of 8.8%) but a higher yield strength. This paper aims at studying the properties of the different tempers of Al 6061 subjected to varying heat-treating parameters (such as artificial aging temperatures and durations, step aging temperatures and durations) and subsequently the determination of optimum parameters to strike a balance between strength and formability.