Welding Standards For Aluminum Alloys
Aluminum alloys are a common material used in many projects from automobile components to aerospace components. These materials offer superior strength and corrosion resistance, making them ideal for many welding applications. The welding process for aluminum alloys is slightly different from other metals and requires special considerations to ensure a strong and reliable joint is produced. This article will discuss the various welding standards for aluminum alloys, as well as their application and importance to welders.
The American Welding Society (AWS) is the international governing body for welding standards. This organization regulates the standards for all welding techniques, materials, and processes. For aluminum alloys, the AWS has developed several standards that must be followed when welding these materials, including welding current, arc temperature, and shield gas type. With aluminum alloys, it is also important to select the appropriate filler material and wire diameter. This information is found in AWS documents and should be consulted before beginning any welding project.
Aluminum alloys behave differently than steel when subjected to heat, as aluminum does not harden with heat which means it is much easier to deform and crack. Therefore, welding parameters, techniques, and filler materials must all be chosen carefully to prevent against cracking, burning, and other defects. Welders should use the lowest possible welding current, as well as the lowest arc temperature, to help reduce these potential issues.
When welding aluminum alloys, a release agent should be used to reduce the chance of metal embrittlement. This release agent helps to prevent oxidation and creates a coating on the metal that prevents welding defects. Additionally, the use of a “no-clean” flux should be avoided, as these fluxes contain chlorides that can cause corrosion and material breakdown.
The most common welding technique used on aluminum alloys is Gas Metal Arc Welding (GMAW). This process involves an electric arc that melts both the base and filler metal, creating a molten pool from which the joint is formed. This welding process is characterized by its high speed, simplicity, and ability to produce high-quality welds.
When using GMAW to weld aluminum alloys, the most important consideration is the choice of shield gas. Shielding gases work to protect the weld from oxygen, which can cause an ineffective weld that lacks strength and integrity. The most commonly used shielding gases for GMAW aluminum welding are 100% Argon and a 25%/75% Argon/Helium mixture.
In summary, aluminum alloys are commonly used in many projects and welding applications. Welding standards must be followed to ensure the highest quality welds. The American Welding Society has developed standards for aluminum alloys that include welding current, arc temperature, and shield gas type. Release agents and no-clean fluxes must also be avoided. Gas Metal Arc Welding is the most widely used welding method on aluminum alloys and is characterized by its speed and high-quality results. Shielding gases are an important factor when it comes to GMAW aluminum welding, with the most common being Argon and a 25%/75% Argon/Helium mixture. Following these standards and precautions will ensure the strongest and most reliable welds for any aluminum alloy project.
