1 Introduction
2 Application and Performance of Al–Li Alloy Extrusion Profiles
2.1 Application of Al–Li Alloy Extrusion Profiles
Generation | Alloy grade—Temper | Substituting for | Application | ||
---|---|---|---|---|---|
Parts | Representative equipment | ||||
First | 1420-T6 | ‒ | ‒ | Soviet aircraft (MiG and SU series) | |
1421- | ‒ | ‒ | |||
Second | 8090-T8511 | 7075-T73511 | ‒ | EH101 | |
8090- | Stringers | Mirage fighter | |||
2090-T86 | 7075-T6 | ‒ | EH101, EF2000, Rafale | ||
2090- | Fuselage frames, floor beams | MD-11, C17 | |||
2090-T86(T8E46) | 2219-T87 | Stiffened panel | Space Shuttle external tank (possible) | ||
2091- | ‒ | ‒ | EH101 helicopter; A330/340 | ||
Third | |||||
Damage tolerant | 2099-T81 | 2024-T3511 2026-T3511 2024-T4312 6110-T6511 | Fuselage frames; Lower wing stringers | ||
2076-T8511 | Fuselage floor beams; Seat rails, frames, stringers; Upper/Lower wing stringers | A380 | |||
Medium/high strength | 2099-T83/T8E67 | 7075-T73511 7075-T79511 7050-T7451 7150-T6511 7175-T79511 7055-T77511 7055-T79511 | Fuselage floor beams, seat rails, stringers; Upper wing stringers | A380, C919 | |
2099-T8511 | |||||
2196-T8511 | Fuselage floor beams, seat rails, stringers | A380, C919 | |||
2055-T8E83 | Fuselage floor beams, seat rails; Upper wing stringers | A380 | |||
2065-T8511 | Lower wing stringers | A380, Ares I | |||
2195-T8, 2096-T8 | 2219-T87 | Stiffened panel | Space Shuttle external tank (possible) | ||
Fourth | X2A66 | 2024 | Integral panel extrusion | - |
2.2 Important Mechanical Properties of Al–Li Alloy Extrusion Profile
Alloy | Temper | Profile and testing positions | Testing orientation | E (GPa) | Strength (MPa) | EL (%) | Ref. | Ref. for DMP | ||
---|---|---|---|---|---|---|---|---|---|---|
TY | UTS | CY | ||||||||
1420 | ‒ | L | 76.4 | 312 | 432 | ‒ | 10.2 | [21] | [21] | |
2090 | T6 | L | ‒ | ~ 750 | ‒ | ‒ | ‒ | [22] | ||
L | ‒ | ~ 630 | ‒ | ‒ | ‒ | |||||
8090 | T6 | L | ‒ | ~ 550 | ‒ | ‒ | ‒ | [22] | ||
L | ‒ | ~ 440 | ~ 515 | ‒ | ‒ | [25] | ||||
L | ‒ | ~ 420 | ~ 500 | ‒ | ‒ | |||||
8091 | T6 | L | ‒ | ~ 630 | - | ‒ | ‒ | [22] | ||
L | ‒ | ~ 495 | ~ 555 | ‒ | ‒ | [25] | ||||
L | ‒ | ~ 440 | ~ 510 | ‒ | ‒ | |||||
2099 | T83 | L | ‒ | ~ 600 | ~ 630 | 622 | ‒ | |||
45o | ‒ | ~ 475 | ~ 425 | 472 | ‒ | |||||
T | ‒ | ~ 445 | ~ 505 | 435 | ‒ | |||||
L | ‒ | ~ 475 | ~ 535 | 483 | ‒ | |||||
45o | ‒ | ~ 425 | ~ 480 | 393 | ‒ | |||||
T | ‒ | ~ 455 | ~ 505 | 520 | ‒ | |||||
L | ‒ | ~ 590 | ~ 600 | 561 | ‒ | |||||
45o | ‒ | ~ 445 | ~ 485 | 397 | ‒ | |||||
T | ‒ | ~ 490 | ~ 525 | 445 | ‒ | |||||
2196 | T8511 | L | 73.17 | 519.93 | 592.23 | ‒ | 6.97 | [30] | ||
L | 79.85 | 526.97 | 602.08 | ‒ | 7.35 | |||||
2195 | T83 | L | ‒ | ~ 620 | ~ 645 | ‒ | ~ 10.5 | [31] | ||
45o | ‒ | ~ 500 | ~ 540 | ‒ | ~ 9 | |||||
T | ‒ | ~ 520 | ~ 560 | ‒ | ~ 8 | |||||
L | ‒ | ~ 580 | ~ 600 | ‒ | ~ 11 | |||||
45o | ‒ | ~ 505 | ~ 555 | ‒ | ~ 16 | |||||
T | ‒ | ~ 590 | ~ 640 | ‒ | ~ 13 |
3 Extrusion Process of Al–Li Alloy Profile
3.1 Conventional Manufacturing Process of Extruded Profiles
3.2 Extrusion Process of the Stiffened Panel with Large-Size
4 Influence of Manufacturing Processes on the Microstructure and Properties of Al–Li Alloy Profiles
4.1 Homogenization of Al–Li Alloy Billet
4.2 Evolutions of Microstructure and Mechanical Properties During the Al–Li Alloys Extrusion
4.2.1 Effects of Extrusion Process on Microstructure and Properties
4.2.2 Microstructure Prediction and Control during Hot Deformation of the Al–Li Alloys
4.2.3 Hollow Profile Extrusion of Al–Li Alloys
4.3 Heat Treatments of Al–Li Alloy Extrusion Profile
4.3.1 Solid Solution and Quenching Processes
4.3.2 Aging Strengthening of Al–Li Alloys
Precipitates | Lattice types | Lattice constants (nm) | Orientation relationships | Characteristics |
---|---|---|---|---|
\({\theta^{\prime\prime}}\) (Al2Cu) | Tetragonal | a = 0.404, c = 0.78 | \(\left( {100} \right)_{\text{Al}} //\left( {100} \right)_{{{\theta^{\prime\prime}}}}\) \(\left[ {001} \right]_{\text{Al}} //\left[ {001} \right]_{{{\theta^{\prime\prime}}}}\) | Coherent, plate-like |
\({\theta^{\prime}}\) (Al2Cu) | Tetragonal | a = 0.404, c = 0.58 | \(\left( {100} \right)_{\text{Al}} //\left( {100} \right)_{{{\theta^{\prime}}}}\) \(\left[ {001} \right]_{\text{Al}} //\left[ {001} \right]_{{{\theta^{\prime}}}}\) | Semi-coherent, lath-like |
\({\delta^{\prime}}\) (Al3Li) | Cubic (L12) | a = 0.401 | Cube-Cube | Coherent, ordered, spherical and metastable |
\(\updelta\) (AlLi) | Cubic (B32) | a = 0.637 | \(\left( {100} \right)_{\text{Al}} //\left( {100} \right)_{\updelta}\) \(\left( {111} \right)_{\text{Al}} //\left( {011} \right)_{\updelta}\) | Incoherent, spherical |
\({\text{T}}_{1}\) (Al2CuLi) | Hexagonal | a = 0.497, c = 0.935 | \(\left( {111} \right)_{\text{Al}} //\left( {0001} \right)_{{{\text{T}}_{1} }}\) \(\left[ {211} \right]_{\text{Al}} //[1120]_{{{\text{T}}_{1} }}\) \([110]_{\text{Al}} //[1010]_{{{\text{T}}_{1} }}\) | Semi-coherent, plate-like |
\({\text{T}}_{\text{B}}\) (Al7.5Cu4Li) | Cubic (CaF2) | a = 0.583 | \(\left( {110} \right)_{\text{Al}} //\left( {100} \right)_{{{\text{T}}_{\text{B}} }}\) \(\left( {001} \right)_{\text{Al}} //\left( {001} \right)_{{{\text{T}}_{\text{B}} }}\) | Lath-like |
\({\text{T}}_{2}\) (Al6CuLi3) | Cubic (Uncertainty) | a = 1.391 | – | Icosahedral symmetry |
\({\text{S}}^{\prime}/{\text{S}}\) (Al2CuMg) | Orthorhombic | a = 0.401, b = 0.925;c = 0.715 | \(\left( {100} \right)_{\text{Al}} //\left( {100} \right)_{\text{S}^{\prime}}\) \(\left[ {021} \right]_{\text{Al}} //\left[ {010} \right]_{\text{S}^{\prime}}\) \([012]_{\text{Al}} //[001]_{\text{S}^{\prime}}\) | Semi-coherent, rod or plate-like |
\({\beta^{\prime}}\) (Al3Zr) | Cubic (L12) | a = 0.405 | Cube-Cube | Coherent, ordered, spherical and dispersed |
\(\varOmega\) (Al2Cu) | Orthorhombic | a = 0.496, b = 0.856, c = 0.848 | \(\left( {211} \right)_{\text{Al}} //\left( {100} \right)_{\varOmega }\) \(\left( {110} \right)_{\text{Al}} //\left( {010} \right)_{\varOmega }\) \(\left( {111} \right)_{\text{Al}} //\left( {001} \right)_{\varOmega }\) | Thin plate-like |
\(\upsigma\) (Al5Cu6Mg2) | Cubic | a = 0.827 | – | Incoherent, square block |