Brad93
Member
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- 17,511
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- Essex, United Kingdom
Hi guys,
Had one or two welds hot crack minutes after welding, I think it is due to filler metal choice.
The two metals are dissimilar aluminium alloys, namely, 5251 Sheet and 5754 Treadplate H114.
Now I've read "The Welding of Aluminium & Its Alloys" by Gene Mathers, and the dissimilar metals table doesn't show 5754.
Looking on Aalco's website, I should be using 5356 for welding 5251 to itself or other 5000 series alloys, is this correct?
"The recommended filler wire is 5356 when welding alloy 5251 to itself, 6XXX series alloys, 7XXX series alloys and most other 5XXX alloys."
Now my 5251 sheet should be 1.7-2.4% Magnesium and the 5754 should be 2.6-3.6%. Is this where the problem lies? Excess magnesium?
On another note:
If I am welding 5251 to 6082, the table in the book doesn't list a suitable filler metal, should this be avoided?
I used 4043 filler for 5754 to 6082 and had no issues.
However I've since seen in the book that this isn't advisable since alloys containing more than 2% silicon such as 5754 can be brittle due to the formation of Mg3Si
Luckily nothing structural going on here to worry about just some toolboxes.
Looking forward to your thoughts, @hotrodder, Pete I'm sure you will know the answer.
Best regards
Had one or two welds hot crack minutes after welding, I think it is due to filler metal choice.
The two metals are dissimilar aluminium alloys, namely, 5251 Sheet and 5754 Treadplate H114.
Now I've read "The Welding of Aluminium & Its Alloys" by Gene Mathers, and the dissimilar metals table doesn't show 5754.
Looking on Aalco's website, I should be using 5356 for welding 5251 to itself or other 5000 series alloys, is this correct?
"The recommended filler wire is 5356 when welding alloy 5251 to itself, 6XXX series alloys, 7XXX series alloys and most other 5XXX alloys."
Now my 5251 sheet should be 1.7-2.4% Magnesium and the 5754 should be 2.6-3.6%. Is this where the problem lies? Excess magnesium?
On another note:
If I am welding 5251 to 6082, the table in the book doesn't list a suitable filler metal, should this be avoided?
I used 4043 filler for 5754 to 6082 and had no issues.
However I've since seen in the book that this isn't advisable since alloys containing more than 2% silicon such as 5754 can be brittle due to the formation of Mg3Si
Luckily nothing structural going on here to worry about just some toolboxes.
Looking forward to your thoughts, @hotrodder, Pete I'm sure you will know the answer.
Best regards