Aluminium welding

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Aluminium welding

Post by ROB. THOMASSON » Sat Nov 02, 2019 10:56 am

I have a friend in the states who has found the Gypsy crank cases are 14% zinc. This could explain the difficulties in welding them. Does anyone have knowledge of welding this stuff. I presume a high zinc rod and a good TIG isn't the answer!

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Re: Aluminium welding

Post by longman » Sat Nov 16, 2019 12:28 pm

Found this info.

The 7xxx series (aluminum-zinc-magnesium) alloys exhibit a wide range of crack sensitivity during the welding. Alloys 7005 and 7039, with a low copper content (<0.1%), have a narrow melting range and can be readily joined with the high magnesium filler alloys 5356, 5183 and 5556. The 7xxx series alloys that possess a substantial amount of copper, such as 7975 and 7178, have a very wide melting range with a low solidus temperature and are extremely sensitive to weld cracking when are welded.
Phil Trangmar

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