Coated electrodes and welding wires are available for all grades of 
 stainless steel.  The following table lists the normal, and when there 
 is one, a generally acceptable alternate selection.  Acceptable 
 alternates are those that have strength and corrosion resistance equal 
 to or greater than the base metal.  The proper AWS designation for 
 electrodes is the alloy designation preceded by E, for example, E 308; 
 for bare wires it is ER as, ER 308.  The AWS designation should be used 
 for designating filler materials as there are slight differences in 
 filler metal and base metal composition.  For example, type 304L is 
 welded with E308L or ER308L, not 304L.


    FILLER METALS FOR WELDING STAINLESS STEELS

Base Metal         Coated Electrode SMAW      Welding Wire GTAW/GMAW
                   Normal    Alternate          Normal    Alternate

201                E 308                        ER 308
410                E 410     E 410 NI Mo        ER 410
430                E 430                        ER 430
301 & 302          E 308                        ER 308
304                E 308     E 308H / E 347     ER 308      ER 347
304L               E 308L    E 347              ER 308L     ER 321/ER 347
321                E 321     E 347 / E 308L     ER 347      ER 347/ER 308L
347                E 347                        ER 347
316                E 316     E 317              ER 316      ER 317
316L               E 316L    E 317L             ER 316      ER 317L
317L               E 317L    E 904L             ER 317L     ER 904L
904L               Alloy 625 E NiCrMo 3         Alloy 625   ER NiCrMo 3
329                E 312Mo                      ER 312Mo
309                E 309     E 310              ER 309      ER 310
310                E 310                        ER 310
330                E 330                        ER 330
                
                WELD OVERLAYS

Carbon steel       E 309 or E 310 to match 304  ER 309 or ER 310
Carbon steel       E 309LMo to match 316L       ER 309LMo
Steel Mill Rolls   E 420                        ER 420

There are a number of unsatisfactory combinations.  Two deserve special
 mention.  First, the lower strength of the L grades limits their 
 usefulness as a filler metal for the standard grades.  Second, the lower 
 corrosion resistance of the Mo free grades can lead to preferential 
 corrosion of the weld metal should they be used as filler metal for the 
 Mo containing grades.


Additional information on welding of stainless steel is available in:
     "Welding of Stainless Steels and Other Methods of Joining", 
       available from NiDI, Literature Item 9 002.

     "Welding Handbook", American Welding Society, 550 NW Le Jeune Road, 
      P.O. Box 351040, Miami, FL 33135.

     "Metals Handbook", Ninth Edition, Volume 6, Welding, Brazing
      and Soldering, Metals Park, Ohio 44073.