7xxx aluminum alloy products

Abstract

New 7xxx aluminum alloys are disclosed. The new 7xxx aluminum alloys may comprise from 5-10 wt. % Zn, 1-3 wt. % Mg, 1-3 wt. % Cu, a thickness of at least 2 inches, from 10% to 40% recrystallized grains, and an average grain size of at least 300 micrometers. The new 7xxx aluminum alloys may have recrystallized areas and the ratio of intercept distances for the recrystallized areas to the average to grain size may be from 0.5 and 2.0. In some embodiments, at least some recrystallized grains are located on a periphery of unrecrystallized grains. The recrystallized grains may be achieved at least partially due to (i) the use of not greater than 0.11 wt. % Zr in the 7xxx aluminum alloy product, (ii) particle stimulated nucleation, or (iii) both.

What is claimed is: 
     
         1 . A 7xxx aluminum alloy plate product, wherein the 7xxx aluminum alloy plate product comprises:
 (a) from 5-10 wt. % Zn, 1-3 wt. % Mg, and 1-3 wt. % Cu;   (a) a thickness of at least 2 inches;   (b) from 10% to 40% recrystallized grains;   (c) an average grain size (d-bar) of at least 300 micrometers, wherein the average grain size is an area-weighted average circular equivalent diameter grain size; and   (d) a ID:d-bar ratio of from 0.5 and 2.0, wherein the ID:d-bar ratio is a ratio of (A) the average intercept distance (ID) to (B) the average grain size (d-bar) of the 7xxx aluminum alloy plate product; wherein the average intercept distance (ID) is the average distance between recrystallized areas of the 7xxx aluminum alloy plate product;   wherein at least some recrystallized grains are located on a periphery of unrecrystallized grains; and   wherein the recrystallized grains are achieved at least partially due to (i) the use of not greater than 0.11 wt. % Zr in the 7xxx aluminum alloy plate product, (ii) particle stimulated nucleation, or (iii) both.   
     
     
         2 . The 7xxx aluminum alloy plate product of  claim 1 , wherein the 7xxx aluminum alloy plate product comprises from 0.03 to 0.10 wt. % Zr. 
     
     
         3 . The 7xxx aluminum alloy plate product of  claim 1 , wherein the 7xxx aluminum alloy plate product comprises from 0.03 to 0.07 wt. % Zr. 
     
     
         4 . The 7xxx aluminum alloy plate product of  claim 1 , wherein the 7xxx aluminum alloy plate product has a thickness of from 3 to 12 inches. 
     
     
         5 . The 7xxx aluminum alloy plate product of  claim 1 , wherein the 7xxx aluminum alloy plate product has thickness of from 4 to 10 inches. 
     
     
         6 . The 7xxx aluminum alloy plate product of  claim 1 , wherein the 7xxx aluminum alloy plate product comprises from 20% to 30% recrystallized grains. 
     
     
         7 . The 7xxx aluminum alloy plate product of  claim 1 , wherein the average grain size is at least 350 micrometers. 
     
     
         8 . The 7xxx aluminum alloy plate product of  claim 1 , wherein the ID:d-bar ratio is from 0.8 to 1.7. 
     
     
         9 . The 7xxx aluminum alloy plate product of  claim 1 , wherein the ID:d-bar ratio is from 1.0 to 1.4. 
     
     
         10 . The 7xxx aluminum alloy plate product of  claim 1 , wherein the 7xxx aluminum alloy plate product realizes improved properties over a compositionally equivalent aluminum alloy plate product at equivalent longitudinal strength;
 wherein the compositionally equivalent aluminum alloy plate product comprises 0.11-0.13 wt. % Zr, and wherein the compositionally equivalent aluminum alloy plate product is of equivalent gauge to the 7xxx aluminum alloy plate product;   wherein the improved properties are selected from the group consisting of: LT elongation, ST elongation, T-L K IC  fracture toughness, S-L K IC  fracture toughness, and combinations thereof;   wherein the equivalent longitudinal strength is that the 7xxx aluminum alloy plate product realizes a TYS-L of not more than 10 MPa lower than the TYS-L of the compositionally equivalent aluminum alloy plate product;   wherein the improved properties are selected from the group consisting of LT elongation properties, T-L K IC  properties, ST elongation properties, and S-L K IC  properties.   
     
     
         11 . The 7xxx aluminum alloy plate product of  claim 10 , wherein the improved properties are LT elongation properties, wherein the 7xxx aluminum alloy plate product realizes at least 1% higher LT elongation, or at least 2% higher LT elongation, or at least 3% higher LT elongation, or at least 4% higher LT elongation, or at least 5% higher LT elongation, or at least 6% higher LT elongation, or at least 7% higher LT elongation, or at least 8% higher LT elongation, or at least 9% higher LT elongation, or at least 10% higher LT elongation, or at least 15% higher LT elongation, or at least 20% higher LT elongation, or at least 25% higher LT elongation, or at least 30% higher LT elongation, or at least 35% higher LT elongation, or at least 40% higher LT elongation;
 wherein the higher LT elongation is calculated as: [(the 7xxx aluminum alloy plate LT elongation)/(the compositionally equivalent aluminum alloy plate LT elongation)]−1]*100%.   
     
     
         12 . The 7xxx aluminum alloy plate product of  claim 10 , wherein the improved properties are T-L K IC  properties, wherein the 7xxx aluminum alloy plate product realizes at least 1% higher T-L K IC  properties, or at least 2% higher T-L K IC  properties, or at least 3% higher T-L K IC  properties, or at least 4% higher T-L K IC  properties, or at least 5% higher T-L K IC  properties;
 wherein the higher T-L K IC  property is calculated as: [(the 7xxx aluminum alloy plate T-L K IC )/(the compositionally equivalent aluminum alloy plate T-L K IC )]−1]*100%.   
     
     
         13 . The 7xxx aluminum alloy plate product of  claim 10 , wherein the improved properties are ST elongation properties, wherein the 7xxx aluminum alloy plate product realizes at least 1% higher ST elongation, or at least 2% higher ST elongation, or at least 3% higher ST elongation, or at least 4% higher ST elongation, or at least 5% higher ST elongation, or at least 6% higher ST elongation, or at least 7% higher ST elongation, or at least 8% higher ST elongation, or at least 9% higher ST elongation, or at least 10% higher ST elongation, or at least 15% higher ST elongation, or at least 20% higher ST elongation;
 wherein the higher ST elongation is calculated as: [(the 7xxx aluminum alloy plate ST elongation)/(the compositionally equivalent aluminum alloy plate ST elongation)]−1]*100%.   
     
     
         14 . The 7xxx aluminum alloy plate product of  claim 10 , wherein the improved properties are S-L Kc properties, wherein the 7xxx aluminum alloy plate product realizes at least 1% higher S-L K IC  properties, or at least 2% higher S-L K IC  properties, or at least 3% higher S-L K IC  properties, or at least 4% higher S-L K IC  properties, or at least 5% higher S-L K IC  properties or at least 6% higher S-L K IC  properties, or at least 7% higher S-L K IC  properties, or at least 8% higher S-L K IC  properties, or at least 9% higher S-L K IC  properties, or at least 2% higher S-L K IC  properties, or at least 10% higher S-L K IC  properties, or at least 11% higher S-L K IC  properties, or at least 12% higher S-L K IC  properties;
 wherein the higher S-L K IC  property is calculated as: [(the 7xxx aluminum alloy plate S-L K IC )/(the compositionally equivalent aluminum alloy plate S-L K IC )]−1]*100%.   
     
     
         15 . The 7xxx aluminum alloy plate product of  claim 1 , wherein the 7xxx aluminum alloy has a composition consistent with AA7050, wherein the AA7050 consistent alloy may include from 0 to 0.11 wt. % Zr. 
     
     
         16 . The 7xxx aluminum alloy plate product of  claim 1 , wherein the 7xxx product aluminum alloy plate product is processed to one of a F, W or T temper, wherein the processing comprises hot rolling the 7xxx aluminum alloy product to one of an intermediate gauge and a final gauge, wherein the hot rolling comprises:
 (a) first rolling in a first direction;   (b) second rolling in a second direction;   wherein the first direction is one of the longitudinal and the transverse direction; and   wherein the second direction is offset by from 45° to 90° from the first direction.