Welding Certification – Structural aluminum applications, AWS D 1.2

What kind of structures are made of aluminium? The first thing that comes to mind is Ships. Aluminum-hulled vessels are increasingly looking for military applications, as well as for the commercial transport.

Why? Aluminum is lighter and that saves fuel and increases the speed.

AWS D 1.2 is the structural welding code-aluminum. It not only provides design and weld joint limitations, but also specifies how must be certified welders for welding aluminum.

The main processes used to weld aluminum structures are Gas Tungsten Arc (GTAW), Gas Metal Arc (GMAW) and variable polarity plasma arc (VPPAW). Gas metal arc welding process is the mainstay for shipbuilding, but friction is being investigated as a possibility in the future.

Along with the need to certify the welder, It is especially important to the procedure to be qualified for aluminum structures. Aluminum loses much of its strength to the soldier and the procedure used to weld can significantly affect the result. Normally, It's a struggle to use the input of heat enough to limit porosity, While, at the same time, use the heat input low enough to not change the resistance and other physical properties of the League.

carbon steel will harden if it is heated to a high enough temperature and, then, cooled quickly. That's how we make such knives and blades.

But aluminum is the exact opposite. When it is heated to a high temperature as happens during welding, He immediately begins to lose its hardness, If your heat treatable alloy T6 6061, or 3003 H14. Either way he loses hardness and resistance if it gets hot enough. Rapid quenching after heating only ensures softness.

AWS D 1.2 requires the use of qualified welding procedures to ensure minimal tensile properties are collected in the weld metal, as well as the heat-affected zone.