Stress relief procedure for Al 7075-T6
Stress relief procedure for Al 7075-T6
(OP)
What is the stress relief procedure for Al 7075-T6 including:
1. Temperatures
2. Furnace time at each temperature (perhaps based on inches of thickness or diameter)
3. Furnace atmosphere
4. Cooling procedure
5. Other?
Thanks,
Don Culp
1. Temperatures
2. Furnace time at each temperature (perhaps based on inches of thickness or diameter)
3. Furnace atmosphere
4. Cooling procedure
5. Other?
Thanks,
Don Culp





RE: Stress relief procedure for Al 7075-T6
RE: Stress relief procedure for Al 7075-T6
Don Culp
RE: Stress relief procedure for Al 7075-T6
It also could be that you are experiencing stress corrosion cracking, scc. I would recommend shot peening due to the scc suseptability of T6. It's also a good idea to provide a coating such as anadizing or at least alodine.
It's also wise to send your failed part to a lab for testing. You will gain vast knowledge from the results (cycle counts, etc).
RE: Stress relief procedure for Al 7075-T6
"In general, the precipitation treatments used to obtain the T6 tempers provide only modest reduction in stresses, ranging from about 10 to 35%."
Other options are mechanical stress relief (using tension or compression prior to age hardening), or cold stabilization (cycling of parts above and below room temperature).
You can consider an overage condition (T7) for improved performance.
You can look at geometry changes and surface modification (peening, burninshing) to improve fatigue resistance.
Regards,
Cory
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
RE: Stress relief procedure for Al 7075-T6
RE: Stress relief procedure for Al 7075-T6
RE: Stress relief procedure for Al 7075-T6
What is the process for cold stabilization? Does it improve the fatigue properties? Any particular on-line references?
I looked at matweb.com for 7075-T7. It listed 7075-T73 and 7075-T735x. The listed fatigue strengths are both 21,800 psi versus 23,000 psi for 7075-T6. Is there some other property for which you feel that the T7 would have better performance?
Don Culp
RE: Stress relief procedure for Al 7075-T6
Don Culp
RE: Stress relief procedure for Al 7075-T6
The biggest reason to use T7 is for improved Stress Corrosion Cracking resistance.
T651 means that mechanical stress relief was used between quenching and artificially aging. Usually done on semi-materials (sheet, bar, etc.) with constant cross section, not on final parts.
Regards,
Cory
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.