[ Welding ]
[ Welding ]
austenitic stainless steel , it is still very good . It is welded without preheating treatment but is heated after the weld is complete to preserve its structural integrity . PH stainless is readily welded through standard fusion and resistance methods . Special care is needed during heat treatment to achieve optimum mechanical properties in the weld and the parent material . The matching filler is selected , and heat treatment after welding helps the weld to achieve close similarities to the parent material . The salient features of the mechanism of welding of different categories of stainless steel are shown in Figure 2 .
Welding stainless steel to other metals Stainless steel components are often welded to components made of other metals . Extreme differences in the melting points of metals make them more difficult to join using standard methods . Plain carbon steel - Austenitic stainless steels , e . g . 304 or 316 , are welded to plain carbon steel using MIG and TIG welding . Filler materials are preferred during MIG welding . Due to differences in electrical conductivity between stainless and plain carbon steel , it is difficult to reach the correct weld temperature . Resistance welding can be used if carbon steel is preheated , as it is more electrically conducive and does not heat up as fast as stainless steel .
Figure 2 . Salient features of the welding mechanism of stainless steel
Low carbon plain steel ( mild steel ) - The carbon content in low carbon plain steel ( mild steel ) typically ranges from 0.05 % to 0.25 % by weight . The welding of low carbon steel to stainless steel is not difficult since these two metals have almost similar properties . MIG welding or GMAW is an excellent process to weld stainless steel to low carbon steel . The most important thing is to select the proper wire . The best filler metal for welding stainless steel to low carbon steel is the 309 [ 3 ] . This filler material has low carbon content and a small amount of ferrite to prevent cracking . Grade 309 has enough chromium and nickel to counter the low carbon steel dilution problem . As a result , the deposited weld metal will have excellent corrosion resistance . Medium carbon plain steel - Medium carbon steel containing 0.30-0.60 % carbon and 0.60-1.65 % manganese is stronger than low carbon steel but
The weldability of stainless steel is influenced by its alloying elements .
42 Stainless Steel World December 2023 www . stainless-steel-world . net