Products made of Al-Zn-Mg-Cu alloys with an improved compromise between static mechanical characteristics and damage tolerance
AssigneePechiney Rhenalu
InventorsJulien Boselli, Fabrice Heymes, Frank Eberl, Timothy Warner
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Abstract
The present invention relates to an extruded, rolled and/or forged product made of an aluminum alloy. Alloys of the present invention may comprise (by mass): Zn 6.7-7.5% Cu 2.0-2.8% Mg 1.6-2.2% at least one element selected from the group composed of: i Zr 0.08-0.20% Cr 0.05-0.25% Sc 0.01-0.50% Hf 0.05-0.20% and V 0.02-0.20% Fe+Si<0.20% other elements ≦0.05 each and ≦0.15 total, balance aluminum. Products of the present invention in some embodiments have an improved compromise between static mechanical strength and damage tolerance.
Claims31
A structural element suitable for aeronautical construction made from at least one extruded product comprising an aluminum alloy of the following composition (by mass):
- (a) Zn 6.9-7.3% Cu 2.0-2.8% Mg from 1.6 to less than 2.0% wherein Cu/Mg is at least 1.1
- (b) at least one element selected from the group consisting of:
- Zr 0.08-0.20%, Cr 0.05-0.25%, Sc 0.01-0.50% Hf 0.05-0.60% and V 0.02-0.20%
- (c) Fe+Si<0.20%
- (d) other elements ≦0.05% each and ≦0.15% total,
- (e) remainder aluminum, wherein said product possesses at least one of the following sets of properties measured at about 20° C.:
- (a) a yield stress Rp0.2(L) equal to at least 580 MPa and a measured Kapp(L-T) with W=100 mm equal to at least about 80 MPa√m;
- (b) a yield stress Rp0.2(L) equal to at least 580 MPa and a crack propagation rate da/dn not exceeding about 3×10−3 mm/cycle for ΔK=27 MPa√m;
- (c) a yield stress Rp0.2(L) equal to at least 580 MPa, an ultimate strength Rm(L) equal to at least 600 MPa and a Kapp(L-T) measured with W=100 mm equal to at least about 80 MPa√m;
- (d) an ultimate strength Rm(L) equal to at least 600 MPa and a Kapp(L-T) measured with W=100 mm equal to at least about 80 MPa√m.
A structural element suitable for aeronautical construction made from at least one extruded product comprising an aluminum alloy of the following composition (by mass):
- (a) Zn 6.9-7.3% Cu 2.0-2.8% Mg from 1.6 to less than 2.0% wherein Cu/Mg is at least 1.1
- (b) at least one element selected from the group consisting of:
- Zr 0.08-0.20% Cr 0.05-0.25% Sc 0.01-0.50% Hf 0.05-0.60% and V 0.02-0.20%
- (c) Fe+Si<0.20%
- (d) other elements ≦0.05% each and ≦0.15% total,
- (e) remainder aluminum, wherein said product possesses the following set of properties measured at about 20° C.:
- (f) a yield stress Rp0.2(L) equal to at least 580 MPa, (ii) an ultimate strength Rm(L) equal to at least 600 MPa and (iii) a KIC(L-T) equal to at least 31 MPa√m.
A structural element suitable for aeronautical construction made from at least one extruded product comprising an aluminum alloy of the following composition (by mass):
- (a) Zn 6.9-7.3% Cu 2.0-2.8% Mg from 1.6% to less than 2.0% wherein Cu/Mg is at least 1.1
- (b) at least one element selected from the group consisting of:
- Zr 0.08-0.20% Cr 0.05-0.25%Sc 0.01-0.50% Hf 0.05-0.60% and V 0.02-0.20%
- (c) Fe +Si<0.20%
- (d) other elements ≦0.05% each and ≦0.15% total,
- (e) remainder aluminum, wherein said product possesses the following set of properties measured at about 20° C.:
- (a) a yield stress RP0.2(L) equal to at least 580 MPa, and a measured Kappl(L-T) with W=100 equal to at least about 80 Mpa√m;
- (b) a yield stress RP0.2(L) equal to at least 580 MPa and a crack propagation rate da/dn not exceeding about 3×10−3 mm/cycle for ΔK=27 MPa√m;
- (c) a yield stress RP0.2(L) equal to at least 580 MPa, an ultimate strength Rm(L) equal to at least 600 MPa and a Kappl(L-T) measured with W=100 mm equal to at least about 80 MPa√m.
A structural element suitable for aeronautical construction made from at least one extruded product comprising an aluminum alloy of the following composition (by mass):
- (a) Zn 6.9-7.3% Cu 2.0-2.8% Mg 1.8-1.91% wherein Cu/Mg is at least 1.1
- (b) at least one element selected from the group consisting of:
- Zr 0.08-0.20% Cr 0.05-0.25%, Sc 0.01-0.50% Hf 0.05-0.60% and V 0.02-0.20%
- (c) Fe +Si<0.20%
- (d) other elements ≦0.05% each and ≦0.15% total,
- (e) remainder aluminum, wherein said product possesses the following set of properties measured at about 20° C.:
- (a) a yield stress Rp0.2(L) equal to at least 580 MPa, and a measured Kappl(L-T) with W=100 mm equal to at least about 80 Mpa√m;
- (b) a yield stress Rp0.2(L) equal to at least 580 MPa and a crack propagation rate da/dn not exceeding about 3×10−3 mm/cycle for ΔK=27 MPa√m;
- (c) a yield stress Rp0.2(L) equal to at least 580 MPa, an ultimate strength Rm(L) equal to at least about 580 MPa and a Kappl(L-T) measured with W=100 mm equal to at least about 80 MPa√m;
- (d) an ultimate strength Rm(L) equal to at least 600 MPa and a Kapp(L-T) measured with W=100 mm equal to at least about 80 MPa√m.
A structural element suitable for aeronautical construction made from at least one extruded product comprising an aluminum alloy of the following composition (by mass):
- (a) Zn 6.9-7.3% Cu 2.0-2.8% Mg from 1.6 to less than 2.0% wherein Cu/Mg is at least 1.1
- (b) at least one element selected from the group consisting of:
- Zr 0.08-0.20%, Sc 0.01-0.50% Hf 0.05-0.60% and V 0.02-0.20%
- (c) Fe+Si<0.20%
- (d) other elements≦0.05% each and≦0.15% total,
- (e) remainder aluminum, wherein said product possesses the following set of properties measured at about 20 C.:
- a yield stress Rp0.2(L) equal to at least 580 MPa, an ultimate strength Rm(L) equal to at least 600 MPa and a measured Kapp(L-T) with W=100 mm equal to at least about 80MPa√m and a KIC(L-T) equal to at least 31 MPa√m.
Dependencies are inferred from the claim text.