solution treat for aluminium below minimum temp by 1.5C 1

[King-K]

i have an aluminum alloy 1xxx which had a set temperature of 529 +/-4C Solution treat however the load had a temperature of only 523. can i do another solution treatment to reset or do i have to age and then run the whole cycle again i.e. solution treat followed by age?

would this have an effect on properties?

 

[metengr]

The 1XXX series aluminum are not heat treatable. You mean annealing or other aluminum alloy?

http://www.asminternational.org/doc...inum.pdf/d8b67b75-1114-4279-b66e-fec86c62a880

 

[King-K]

it is an aluminium alloy sorry not a 1xxx.

 

[metengr]

What alloy? You have a nonconformance, with two dispositions; either repeat the re-solution anneal within the specified temperature range or continue with the aging treatment and determine if the mechanical properties are acceptable.

 

[tbuelna]

I would agree with metengr. The process was apparently non-conforming and thus requires some corrective action.

There was no mention of what process spec (if any) was used for this HT procedure. I checked an old copy of MIL-H-6088 and the only wrought materials with a solution HT temp in the range noted were 6951 sheet and 2618 forgings. Section 6.3.3.4 of MIL-H-6088 talks about potential issues when the solution heat treat temp is below the minimum specified. Section 3.6.2 covers re-solution heat treatment, including limits on the number of times re-solution heat treatment is permitted.

Hope that helps.
Terry