Grade 409 sheets of steel must be pre-heated to temperatures of 150 to 260°C before welding. Although grade 430 and 409 filler rods or electrodes can be used during welding of grade 409 sheets of steel, Grade 309 electrodes or filler rods are strongly recommended by AS 1554.6. Care should be taken in order to weld grade 409 steel with minimum heat, in order to mitigate grain growth.
Ductility of welded products can be enhanced by annealing post-welding at temperatures of 760 to 815°C. However. This is not required for lightweight welded products. Welding of exhaust tubing of automobiles is performed without filler rods.
The typical applications of grade 409 stainless sheets of steel are listed below:
·Automotive exhaust tubing
·Catalytic converter systems