Compatibility Chart

12 | www.lincolnelectric.com
Introduction
............................................................................................................................................................
1.4 TEMPER DESIGNATIONS
The information above allows an aluminum alloy to be recognized by its
chemistry, but not by the heat treatment or mechanical properties. To show these
properties, temper designations are assigned. The complete designation of an
alloy might be 6061-T6 or 5083–H114. Most of these designations are different for
heat-treatable and nonheat-treatable alloys; however, two common designations
apply to all alloys:
» “O” Temper (not zero). When an alloy is given this designation, the supplier has
annealed the alloy, typically at 650-750°F (343-300°C), and it is as soft as possible.
» “F” Temper. When an alloy is supplied in this temper, it is supplied “as
fabricated”. This means the supplier is guaranteeing that the chemistry of the
material meets the chemical requirements for the specified alloy, but there are
no claims regarding the mechanical properties of the alloy. This temper is often
specified by fabricators who subsequently forge or form the supplied material
and establish mechanical properties by heat treatment after forming.
To discuss the remainder of the temper designations, we need to discuss the
heat-treatable and nonheat-treatable alloys.
1.4.1 NONHEATTREATABLE ALLOYS  STRAINHARDENED DESIGNATIONS
These alloys cannot be strengthened by heat treatment. However, they can be
strengthened by cold working, also called strain hardening. If an aluminum alloy is
deformed at elevated temperatures, 600°F (315°C) or higher, little or no
strengthening takes place. However, if the alloy is deformed at lower temperatures,
it will gain strength. In general:
» The more the alloy is deformed, the stronger it gets. Finally, at some point, the
alloy will have no ductility and will fracture.
» The higher the alloy content, the more it will gain strength by being deformed.
Both of these phenomena are shown in Figure 1-1.