Why Austenitic Stainless Steel Backing?

By Rory Jones Date 05-29-2003 04:44

When temporary steel backing is used for aluminum groove welds, the AWS D1.2 Aluminum Welding Code requires austenitic stainless steel to be used. In our application we will be MIG welding 1/4” thick aluminum partial joint penetration groove welds with a root gap not to exceed 1/32” and a 1/16“ root face. What problems might we encounter if we just use clean low carbon steel for temporary backing? Can anyone refer me to research on using different types of steel for temporary backing for aluminum welds?

By Kamaruzaman (*)

Date 05-31-2003 06:22

may be hard to remove as harden material or carbon contaminated to Al

By brande

Date 06-01-2003 07:21

The only reason that comers to mind is that is very difficult to get aluminum to stick or weld to stainless.Carbon steel can stick, sometimes, due to naturally occuring contaminants like mill scale and the like.
FWIW-if the code calls for a certain or anything else, you would be wise to follow the code, especially if an inspector is involved.

Good Luck
brande