US 12,221,677 B2
Dispersoids 7XXX alloy products with enhanced environmentally assisted cracking and fatigue crack growth deviation resistance
Zhengdong Long, Spokane, WA (US); Philippe Gomiero, Spokane Valley, WA (US); Ravi Rastogi, Liberty Lake, WA (US); Robert A. Matuska, Heath, OH (US); Garry R. McDaniel, Newark, OH (US); and Jason N. Scheuring, Spokane, WA (US)
Assigned to Kaiser Aluminum Fabricated Products, LLC, Foothill Ranch (CA)
Filed by KAISER ALUMINUM FABRICATED PRODUCTS, LLC, Foothill Ranch, CA (US)
Filed on Sep. 20, 2022, as Appl. No. 17/933,633.
Claims priority of provisional application 63/248,690, filed on Sep. 27, 2021.
Prior Publication US 2023/0114162 A1, Apr. 13, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. C22C 21/10 (2006.01); C21D 8/02 (2006.01); C22F 1/053 (2006.01)
CPC C22C 21/10 (2013.01) [C21D 8/0226 (2013.01); C21D 8/0252 (2013.01); C21D 8/0263 (2013.01); C22F 1/053 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A 7xxx aluminum alloy product comprising,
4.0 to 8.5 wt. % Zn,
1.0 to 3.0 wt. % Cu,
1.8 to 3.0 wt. % Mg,
0.08 to 0.15 wt. % Zr as dispersoid element,
0.20 to 0.30 wt. % Mn as dispersoid element,
up to 0.30 wt. % Cr as dispersoid element,
not exceeding a total of 0.35 wt. % incidental elements, and the balance Al, wherein Zr+Cr+Mn ranges from 0.2 to 0.8 wt. % and Zr+Mn ranges from 0.3 to 0.7 wt. %, and
wherein said aluminum alloy product has an Environmentally Assisted Cracking (EAC) survival longer than 60 days under the testing conditions of temperature=70° C., relative humidity=85%, loading stress is 85% of Rp0.2 in ST direction.