Virgil:
        My expertise is not in material science, but I know about welding
since I worked as a welder while in the military. From your information the
weld is not coming apart but the box is cracking at the lips weld, which is
the parts that vibrates the most. So the tungsten bonded the two materials
but is not taking the vibrations well.  It tells me that the part needs to
be reinforced at that point with a button weld, a welded plate or other
manner..
        Regards,
        Ramon

> -----Original Message-----
> From: Virgil Lenton [SMTP:[log in to unmask]]
> Sent: Friday, September 26, 2003 2:53 PM
> To:   [log in to unmask]
> Subject:      [TN] Aluminum Welding - Wrong Tungsten
>
> Hi all.
>
> I'm hoping you can help me. I know very little about welding. We have
> some .093 aluminum that has been bent into a box shape and then seam
> welded. The seams are then ground smooth. On a few of these units, we have
> noticed what looks like a crack beginning to form at the weld at the lip.
>
> Further investigation has found that the welder used the wrong material to
> make these welds. Apparently, he used tungsten for steel instead of
> tungsten for aluminum.
>
> These boxes hold electronic equipment and are installed in vehicles,
> hence,
> a fair bit of vibration.
>
> What will the ultimate repercussions of this wrong tungsten be on the
> final
> structure of this box? Will the small cracks propagate along the weld? Is
> it likely that we will see these cracks on all units? Is there anything
> else I should be concerned with?
>
> Thanks in advance for any and all replies.
>
> Virgil
>
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