Aluminum spot welding

Date 02-20-2002 17:29

ALCOTEC.

Many in the forum have talked about their seminars. They emphasize the importance of storing aluminum and aluminum alloys (this includes welding consumables). I learned quite a bit regarding Al material storage.

ALCOTEC

By noswal Date 02-20-2002 18:27

Yes thanks DGXL, I have looked into that. Seminars are not until May. I was really looking for an answer on the board.
If I have a 6000 series T4 aluminum coil that has just had its first step (called heat-treatment or sloution heat-treatment) and has done its week long strenghtening period termed as "aging or room temperature precipitation" (at the rolling manufacturer), what is the allowable amount of time from leaving the mill to factory floor must it be put through the press?
Many alloys approach stable condition at room temperature, but some alloys, particularly those containing magnesium and silicon or magnesium and zinc (6000 series Mg&Si), continue to "age-harden" for long periods of time at room temperature. If it was to graphed, would the curve be exponential? What is the storage time alotted for a coil prior to being pressed and welded? Is there a cut off?

By DGXL

Date 02-21-2002 05:13

Nos,
Find out the ASTM specification for that material. The processing standards, chemistry limits, mechanical propeties, etc. should be available there.

e.g.: Alclad 6061 T4 (in plate or sheet form) is ASTM B209.
The applicable ASTM standard should provide an answer for you.

I am sure you are also aware the aging process will be continuous, so don't wait by the oven for the pie to cool.

By noswal Date 02-21-2002 13:39

Thanks once again DGXL,
The ASTM=E646, but tells me nothing about shelf life. I was aware that the aluminum continuously aged but was unsure when the "cut-off" was for usage within my press.
How good of a baker are you? (LOL)
But do appreciate the help, thanks.

Nos