welding 6061 to 5052 1

[berkshire]

Time to ask a quick stupid question.
I have a job where I need to weld a 6061 extrusion to 5052 sheet aluminum. I do not like mixing up these alloys, I find they have a tendency to crack unless the welder is very careful.
Am I better off with a 4043 rod or 5356, this will be tig welding. or is there a better selection of rod for this mixture of alloys.
B.E.

 

[weldtek]

http://www.alcotec.com

 

[berkshire]

weldtek (Materials)
I went there, they seemed to favor the 5356.
It appears to be a toss up between the two rods.
B.E.

 

[weldtek]

I think 5356 is generally recommended because it offers greater strengt, but 4043 is ok for many applications and offers greater crack resistivity.
It is not recommended, however, to mix the two fillers in one joint, say as using 4043 to repair crater cracks in a 5356 deposit. This is due to the brittle intermetallic compound that can form from the combination of high silicon in the 4043 and the high magnesium in the 5356.

 

[berkshire]

weldtek (Materials)
So based on what you are saying, I am less likely to get cracking with 4043 which is what I am most concerned about.
The strength issue is not a concern with this weldment unless of course it cracks.
B.E.

 

[weldtek]

Type 4043 filler will offer better resistivity to cracking, and, for the application you describe, it sounds like a good choice.
.

 

[berkshire]

Thanks a lot Weldtek I will go with the 4043.
B.E.