In the U.S. materials manufacturing plays a massive role in the country’s industry. This includes all sorts of metal fabrication processes like laser cutting, metal bending, metal rolling, and any other stainless steel fabrication, aluminium fabrication and steel fabrication processes. Many of the products of this manufacturing ecosystem include tubing, angles and flat sheets that are about 3/16-inches thick. There has been some debate over the best methods of producing these think welded products. Therefore, a lot of consideration is required and an analysis of the application of the product must be done before determining the best method of welding, shielding the gas, and electrodes to use. A lot of factors are brought to light once a requirement analysis has been done, such as the base material type, its thickness, and condition. Additionally, welding positions and the equipment available to weld the materials also affect the overall decision on the method of welding.
There are some precautions necessary when welding thin materials. Some of these include minimizing distortion and splatter. An additional concern is to ensure a top quality fusion and proper weld without burning through the material.
For plain carbon steel
In the case of plain carbon steel, it allows for a wide range of welding techniques. For some of the thinner materials, gas metal arc welding (GMAW) is recommended in short-circuiting transfer mode. Another option comes in the form of using pulsed GMAW. This, however, requires the use of a shielding gas with high argon content. The use of pulsed GMAW offers the welder more control and a wider range of operating parameters while generating a much lower amount of splatter. Although pulsed GMAW has these benefits, it is not always financially justifiable due to the high cost of the equipment required.
Flux-cored arc welding (FCAW) is another popular method, however, it is not ideal. During the weld, it produces a protective slag layer that must be removed. It also produces more spatter and smokes compared to GMAW.
Finally, the gas tungsten arc welding (GTAW) process. Using this method is perfect for producing high-quality welds without spatter. However, this method requires higher skilled welders and the use of 100 percent argon gas as a shielding gas is a must.
Methods for stainless steel
The primary difference welding plain carbon steel and stainless steel comes when matching proper filler metal to the base material. The use of shielding gases remains similar. For GMAW, a gas with high argon content is required. In the case of FCAW, just like carbon steel, stainless also requires 100 percent carbon dioxide gas or a 75 percent argon with 25 percent carbon dioxide blend.
Aluminum is a different matter
In the case of welding any of the other materials, a clean weld joint is of utmost importance. This is not the case for aluminum as it actually benefits from a pre-weld or brushed joint due to the presence of the heavy oxide layer.
There is no absolute method when it comes to welding, however, the above should set a proper example of choosing the correct method depending on the circumstance.
