Pressure vessels commonly use pure aluminum, aluminum-manganese alloys, and aluminum-magnesium alloys. Aluminum-manganese alloys are deformable and can be strengthened, offering slightly higher strength than pure aluminum. They also possess good formability, corrosion resistance, and welding properties. Aluminum-magnesium alloys are also deformable and can be strengthened.ω(Mg)Generally0.5％~ 7.0Compared to other aluminum alloys, aluminum magnesium alloys have moderate strength, along with good ductility, welding properties, and corrosion resistance.
1. Welding Wire Material
SelectedAluminumWelding wire should ensure that the tensile strength of the weld metal is not less than that of the base material.(Non-heat treated aluminum alloy is in the annealed state, while heat treated aluminum alloy is at the specified/indicated value.)The minimum tensile strength value or specified value, ensuring that the weld metal's ductility and corrosion resistance is not less than or close to the base material, or meets the drawing requirements.
To ensure the corrosion resistance of the welds, it is advisable to use a purity that is similar to or slightly higher than the base material when welding pure aluminum.AluminumWelding wire. When welding aluminum-magnesium alloys or aluminum-manganese alloys, etc., which are corrosion-resistant aluminum alloys, it is advisable to use a welding wire with a magnesium or manganese content similar to or slightly higher than the base material.AluminumWelding Wire.
AluminumWelding wire is available fromGB/T 10858-2008Selected from "Aluminum and Aluminum Alloy Welding Wire," also available with the same chemical composition as wrought aluminum and aluminum alloys.(As per your instruction, there is no Chinese content provided to translate. Therefore, I will return "As per your instruction, there is no Chinese content provided to translate."GB/T 3190-1996"Chemical Composition of Aluminum Alloys and Aluminum Alloys")Selecting from our range of silk materials。
2. Welding Characteristics of Aluminum and Aluminum Alloys
Aluminum is highly reactive and prone to oxidation, forming a dense layer in ambient air at room temperature.A12O3Film, when welding, can cause inclusions, and alumina film also absorbs moisture, which can promote the formation of air holes in the weld seam. During welding, effective protection should be provided for molten metal and high-temperature metal.
The linear thermal expansion coefficient of aluminum is approximately that of steel.2Aluminum has a much higher shrinkage rate during solidification than steel, which makes it prone to the formation of shrinkage cavities, shrinkage porosity, thermal cracks, and higher internal stresses during welding.
Aluminum and its alloys are prone to absorb gases like hydrogen in the molten pool. During the cooling and solidification process after welding, the gases do not have enough time to析出, resulting in gas pores forming in the weld seam.
When the base material is deformed strengthening or solution-aged strengthening, the strength of the weld heat-affected zone will decrease.
3. Aluminum WeldingSilkWelding Methods for Aluminum Pressure Vessels
Aluminum and aluminum alloy applications are numerous. During welding on pressure vessels, tungsten inert gas (TIG) welding and gas shielded metal arc welding (GMAW) are commonly used. These welding methods concentrate heat and have stable arc combustion. Due to the use of inert gas, protection is excellent, making it easy to control impurities and moisture sources, reducing the occurrence of hot cracks and gas pores. The weld quality is superior. TIG welding is generally used for thin plates.PMIGWelding for thick plates.
