Can You Weld Stainless Steel and Mild Steel Together Using a TIG Welder?

Yes, it is possible to weld stainless steel and mild steel together using a TIG (Tungsten Inert Gas) welder. However, using the correct welding settings and filler wire is crucial for ensuring a successful and durable weld. This article will provide detailed guidance on the settings and filler wire required for this type of welding job.

Understanding the Welding Process

When welding stainless steel to mild steel, the primary consideration is the filler wire, also known as the consumables. Unlike mild steel, which requires different welding consumables, stainless steel demands a higher-grade wire. For this purpose, a common choice is 309L welding rod.

Welding Settings

The welding settings for stainless steel and mild steel using a TIG welder are similar. However, the key difference lies in the correct choice of filler wire. To start the welding process, follow these guidelines:

Amp Settings: Use the material thickness multiplied by 35 to determine the appropriate amperage setting. Gas and Rod Choice: Utilize argon gas consistently with the 309L welding rod.

These settings and the correct filler wire will ensure a strong and reliable weld. The heat input during each weld pass must be carefully managed to prevent overheating, which could degrade the properties of the stainless steel.

Additional Considerations

When welding dissimilar materials such as stainless steel and mild steel, several factors need to be taken into account to ensure a successful outcome:

Heat Input Control: The heat input during each weld pass should be kept below 1.5Kj/mm. Additionally, the interpass temperature should not exceed 150 degrees Celsius. Tacking and Constraints: Stainless steel tends to distort more than carbon steel during welding. To mitigate this, additional tacking and constraint measures may be necessary.

Proper Filler Wire for Dissimilar Metals

Using the correct filler wire is essential when welding different types of metals, including stainless steel and mild steel. For best results, use a filler wire with the necessary alloy content to match the components being welded. A commonly recommended choice is 309L welder, which is suitable for mild to stainless steel joints.

Remember, different grades of stainless steel may require different types of filler wire. Always consult the specifications before selecting the filler wire for your specific welding job.

Conclusion

Welding stainless steel and mild steel together using a TIG welder is achievable, provided you use the correct settings and filler wire. By following the guidelines outlined in this article, you can ensure a strong and reliable weld that meets the requirements of your project. Proper preparation, careful control of heat input, and the use of suitable filler wire are key to achieving a successful outcome.