The 2000 series (2xxx) are aluminum–copper wrought alloys that can be precipitation hardened to very high strength with good fatigue resistance and solid machinability.
Signature grades include 2024, 2014, and 2219. They’re the backbone of classic aerospace structures and high-load components.
Corrosion resistance is only moderate and fusion weldability is limited (with 2219 as the key weldable exception). 2xxx are not die-casting alloys, but they pair perfectly with A380 / ADC12 / AlSi10Mg die-cast housings in mixed assemblies.
What is 2000 series aluminum?
The 2xxx family uses copper as the primary alloying element. After solution heat treatment and aging, finely dispersed precipitates increase strength to levels that rival low-alloy steels—at far lower density. These are wrought products (plate, sheet, extrusions, forgings) that are usually machined and then joined mechanically or with specialized welding processes.
Which grades define the 2xxx family?
Below is a fast overview of popular grades and where they fit:
| Alloy | Typical product | What it’s best at | Common uses | Notes |
|---|---|---|---|---|
| 2024 | Sheet, plate, extrusions | High strength + fatigue | Airframe skins, ribs, fittings | SCC-sensitive → often alclad or primed |
| 2014 | Forgings, bar, plate | Strength + machinability | Aerospace fittings, truck frames | Good response in T6/T651 |
| 2124 / 2324 | High-purity plate | Toughness & fatigue vs 2024 | Critical wing/skin panels | Controlled chemistries |
| 2219 | Plate, forgings | Weldable Al-Cu, elevated-temp | Cryogenic tanks, space structures | TIG/EB/FSW; widely documented |
| 2195 (Al-Li) | Plate | Lower density + stiffness | Launch vehicle tanks | Specialized processing |
| 2090/2091/2050 (Al-Li) | Plate, extrusions | Weight saving | Aerospace structures | Program-specific specs |
If you need a machining-friendly bar/forging with high strength, start with 2014. For welded tanks or high-temp service, 2219 leads.
How strong is 2xxx vs 6xxx and 7xxx?
- 2xxx vs 6xxx: 2xxx delivers much higher strength and fatigue resistance; 6xxx wins for extrudability, corrosion resistance, and low cost (frames, general structures).
- 2xxx vs 7xxx: 7xxx can be even stronger (e.g., 7075-T6), but may require tighter corrosion/toughness controls and is less weldable. Choose 2xxx for damage tolerance, hot strength, and established aerospace allowables.
Rule of thumb: If you need steel-like specific strength in a wrought, machinable aluminum—look at 2024/2014. If you need welded high-strength aluminum, look at 2219 or FSW on selected 2xxx/Al-Li.
How does precipitation hardening work (T3/T4/T6/T8)?
- Solution heat treat to dissolve Cu-rich phases.
- Quench to retain a supersaturated solid solution.
- Age (naturally = T4/T3, artificially = T6/T8) to form fine precipitates that block dislocation motion.
- T3/T351: solution heat treated, cold-worked, naturally aged (common for 2024 sheet).
- T6/T651: solution heat treated, artificially aged, stress-relieved (typical for plate, forgings).
- T8/T851: additional cold work before artificial aging for higher strength.
Is 2000 series aluminum weldable?
- General answer: Limited. Many 2xxx grades crack under conventional fusion welding.
- Exception: 2219 is the weldable Al-Cu alloy; widely used for cryogenic/propellant tanks with TIG/EB/FSW.
- Alternatives: Friction stir welding (FSW) for selected joints; brazing where joint geometry allows.
- Best practice: For most 2xxx, rely on mechanical fasteners or bonding rather than fusion welds.
Why is 2024 so popular—and what are its limits?
2024 balances high strength, fatigue performance, and machinability. It’s a classic for skins, frames, and load-bearing fittings. Limits: stress-corrosion cracking and general corrosion require alclad, conversion coatings, primers, or sealants—especially in humid/saline service.
When should I choose 2219 instead of 2024?
Pick 2219 when a structure must be welded and remain strong—e.g., tanks, domes, cryogenic lines, or elevated-temperature components. You trade some strength vs 2024-T3/T351 but gain robust weldability and thermal stability.
What about Al-Li in the 2xxx family?
Aluminum–lithium members of 2xxx offer lower density and higher modulus, enabling significant weight savings. They require tight process control and program-specific specs. Use when mass reduction is a top priority and your certification pathway supports Al-Li.
Does 2xxx resist corrosion well?
Moderate. For long life in aggressive environments:
- Use alclad products where available (e.g., 2024-T3 Alclad).
- Apply conversion coat + primer + topcoat and seal faying surfaces.
- Galvanically isolate from carbon steel/graphite and more noble metals.
Can 2000 series aluminum be die cast?
Short answer: no. The 2xxx family (Al-Cu) is designed as wrought alloys for plate, sheet, extrusions, and forgings that are later machined and heat-treated. High copper content hurts melt fluidity and increases hot-cracking risk in pressure die casting.
If you need a die-cast part, engineers typically choose Al-Si cast alloys with excellent fluidity—most commonly A380, ADC12, or AlSi10Mg. These provide:
- Thin-wall fill and die life suited to high-volume production
- Balanced strength and dimensional stability after aging/impregnation
- Tight-tolerance capability for housings, covers, and brackets
Use 2xxx when you need machined, high-strength wrought components (plates, ribs, fittings) that bolt to or sit inside the cast housing.
How we pair 2xxx parts with die-cast housings (A380 / ADC12 / AlSi10Mg)
We routinely build mixed assemblies that combine wrought 2xxx with die-cast 3xx parts:
- Load path & roles
- Let the die-cast housing (A380/ADC12/AlSi10Mg) provide geometry, threads, EMC shielding, and mass-production efficiency.
- Let the 2xxx plate/forging deliver high strength and fatigue life at fasteners, interfaces, or mounting rails.
- Joining methods
- Mechanical: stainless/Al fasteners with isolation washers; steel threaded inserts in the casting for durability.
- Adhesive/bonding: structural acrylic/epoxy to handle peel; prep with light blast + solvent clean.
- Brazing/FSW: consider 2219 or non-Cu alloys if fusion welds are mandatory; FSW on wrought-to-wrought, then assemble to the casting mechanically.
- Galvanic & corrosion control
- Separate Cu-rich 2xxx from Si-rich castings using non-conductive shims, sealants, or coatings.
- Use alclad/primer on 2024 where appropriate; anodize + seal or conversion coatings on cast surfaces.
- Tolerance & DFM
- Hold precision features on the wrought 2xxx (post-machining).
- Build locating pads into the casting; define a datum scheme where the machined 2xxx controls the critical stack.
- For wide temperature swings, use slotted/oval holes in the 2xxx part to accommodate differential expansion.
- Supply flow
- We cast A380/ADC12/AlSi10Mg, machine both the casting and the 2xxx plate/forging, and deliver assembled with torque records, NDT where required, and certs.
Result: you keep the strength and fatigue performance of 2xxx where it matters, while the die-cast housing delivers cost-effective geometry at volume.
How to specify 2xxx for purchasing
Include the full engineering call-out so suppliers quote apples-to-apples:
- Alloy + temper (e.g., 2024-T351 plate, 2014-T6 forging, 2219-T87 plate)
- Form + size + grain direction (L/T orientation for plate)
- Clad vs unclad, surface finish, coating/primer requirements
- Mechanical targets (UTS, YS, elongation), flatness, residual stress (-T351/-T651 stress-relieved)
- NDT & certs (UT, PT, RT, material test reports), traceability to lot/heat
- Packaging for damage-free delivery
FAQs
Is 2024 stronger than 6061?
Yes. 2024-T3/T351 has significantly higher strength and better fatigue performance than 6061-T6, but with lower corrosion resistance and weldability.
Which 2xxx alloy is weldable?
2219 is the most commonly weldable Al-Cu alloy; it’s used for cryogenic tanks and high-integrity structures.
What tempers are typical for 2xxx?
2024: T3/T351 (sheet/plate), T81/T851 for higher strength. 2014: T6/T651. 2219: T37/T62/T87 depending on process.
Can 2xxx be anodized?
Yes, but protective systems (conversion coat + primer + topcoat) are preferred for corrosion control, especially on 2024.
Can 2xxx be die cast?
No. They’re wrought alloys. Use A380/ADC12/AlSi10Mg for die casting and join to 2xxx components in the assembly.
Need a die-cast housing supplier?
We produce aluminum die castings in A380, ADC12, and AlSi10Mg, then machine and integrate your 2xxx components. Send your drawing—we’ll review DFM, joint options, galvanic control, and tolerance stack-up and quote quickly.
