What weld type is most commonly tested for thermal severity?

The most commonly tested weld type for thermal severity is the fillet weld. This is primarily because fillet welds are extensively used in various structural applications, particularly in the fabrication of steel components. They are often subjected to different stresses and thermal conditions during the welding process, making it essential to evaluate their performance under these conditions.

Thermal severity testing focuses on assessing how a welded joint can withstand varying temperatures, which is crucial in ensuring the integrity and reliability of the weld in service. Since fillet welds can be found in many critical applications, testing their thermal characteristics helps identify potential issues such as distortion, cracking, or other defects that may arise from improper heat input or cooling rates during the welding process.

The other types of welds, while also important in their respective applications, are either less common or not as extensively tested for thermal severity compared to fillet welds. This is due to the specific requirements or standards that prioritize the evaluation of fillet welds in the industry.