Welding Process of 904L Stainless Steel Plate

The welding method for 904L stainless steel plate is the welding process of low carbon duplex austenitic stainless steel. It has two steps: manual tungsten inert gas (TIG) welding and acid pickling passivation of the weld surface.

Firstly, proper preparations are made for the welded joint. Filler metal of the same material as 904L is used, and the weld is cooled with cold water during the welding process. The welding temperature should controlled below 80℃, the welding speed should be maintained at 45-50 centimeters per minute, and the width-to-depth ratio of the weld should be controlled between 1.5:1 and 2:1. The thickness of the weldment should not exceed 12mm.

After that, the weld surface should be subjected to acid pickling passivation. Through this method, welding can be do at low temperature, which avoided problem of internal molecular transformation of 904L stainless steel. Therefore, defects such as brittleness transition, intergran corrosion during welding, and hot cracking can be avoided, and the deformation of the weldment can be controlled. The characteristics of 904L stainless steel, such as resistance to acid, alkali, and high-temperature corrosion, can greatly extend the service life of the stainless steel plate.