Why is Welding Stainless Steel Difficult?

Welding stainless steel can be more difficult, especially for a novice. This is due to the fact that stainless steel will retain heat more efficiently. If there is too much welding heat, then the stainless steel can warp when heating up, or during the cooling process. Also, welding stainless steel can be an unforgiving task as it can blemish and scratch more easily and it is more difficult to hide these imperfections.

man welding steel with flying orange sparks

Welding Stainless Steel

To be successful at welding stainless steel you will need to use the right equipment and the proper technique. To properly weld stainless steel, you will need to:

  1. Put on a welding mask and protective clothing.
  2. Choose an argon-carbon dioxide shielding gas that will work with your specific project. The best mix will contain 98% argon and 2% carbon dioxide.
  3. Identify the specific steel that you have. This can be found by looking at the 3 digit code printed on the piece. If the number is in the 300s it is austenitic steel that is non-magnetic and has a higher percentage of chromium. If it is 410, 420, or 440A it is martensitic steel, which is magnetic and wear-resistant. Steel marked as 409 or 439 is ferritic. This type of steel is magnetic and has a high carbon content.
  4. Pick a filler metal to match the steel. For the best weld, the filler material should have a similar composition to the base metal.
  5. Clean the metal using acetone and a wire brush designed for stainless steel to remove any impurities.
  6. Decide on the joint you want to use to weld. This will be determined by how you want the pieces of metal to be joined.
  7. Secure your metal to your work surface, arranging the pieces in place, and holding them with the proper fixtures and jigs. Proper securing is crucial to ensure a proper and solid weld. If the metal slips at all the joint may become weakened.

 If you have a stainless steel welding project that you want to make sure is done properly Marvel’s Portable Welding has the equipment, the experience, and the skill level to get the job done. Contact us today to discuss the details of your project.