1100-O aluminum is the fully annealed (softest) condition of commercially pure 1100 aluminum. It has undergone a specific heat treatment process to remove all internal stresses, offering maximum ductility, excellent formability, and the lowest mechanical strength among all aluminum tempers. If your project requires heavy forming without the metal tearing, the "O" temper is exactly what you need.
As a reliable aluminum supplier, we constantly see buyers make the mistake of buying standard work-hardened aluminum when they actually need the O temper.
What Does "O Temper" Mean for an 1100-O Aluminum Tube?
The "O" temper stands for Annealed.
When a factory produces an aluminum pipe or sheet, the metal goes through rolling or extrusion machines. This physical pressure causes the internal grain structure of the metal to become tight and stressed. This is called "work hardening." Work-hardened metal is strong but brittle; if you try to bend it sharply, it snaps.
The Annealing Process:
To make an 1100-O aluminum tube, the factory places the work-hardened metal into a massive industrial furnace.
- Heating: The aluminum is heated to approximately 650°F (343°C).
- Holding: It is kept at this temperature so the internal crystal structure can reorganize and relax.
- Cooling: It is allowed to cool down very slowly.
This process completely removes all internal stress. The result is 1100-O: the softest, most relaxed, and most ductile version of the 1100 alloy possible.
Properties of 1100-O Aluminum Pipe
Because 1100-O is a minimum of 99.0% pure aluminum and fully annealed, its mechanical numbers look very different from structural metals. Here is the standard factory data:
| Mechanical Property | Value for 1100-O Aluminum |
| Tensile Strength | 70 – 95 MPa |
| Yield Strength | 20 – 35 MPa |
| Elongation (Ductility) | Highly Excellent (Stretches easily) |
| Hardness (Brinell) | ~ 23 HB (Very soft) |
| Corrosion Resistance | Outstanding (Natural oxide layer) |
Look closely at the Yield Strength (20-35 MPa). Yield strength is the point where metal bends and stays bent. Because this number is so low, you can literally take a small diameter 1100-O aluminum pipe and bend it into a 90-degree angle with your bare hands. It requires very little force to shape.
Why Choose 1100-O Pure Aluminum Round Tube?
- Extreme Formability: It can undergo severe deep drawing or tight-radius bending without the material splitting, cracking, or tearing at the seams.
- Low Tooling Wear: Because the metal is so soft, it puts almost zero stress on your factory's CNC bending machines, stamping dies, or cutting blades. Your tools will last significantly longer.
- Zero Springback: When you bend standard metals, they tend to bounce back a little. 1100-O has almost no springback. When you bend it, it stays exactly where you put it, ensuring high dimensional accuracy for your parts.
- Excellent Surface Quality: The annealed surface is highly uniform, making it perfect for polishing or clear anodizing.
Are you experiencing high scrap rates because your current aluminum tubes are cracking during the bending or flaring process? You might be using the wrong temper. Contact GNEE's engineering team today for a free material consultation. We will supply the exact 1100-O aluminum tube you need to ensure a flawless forming process.
Typical Applications of 1100-O Aluminum
Because 1100-O has low strength but incredible formability and chemical resistance, it dominates specific, non-load-bearing industries.
- Deep Drawn Kitchen Utensils: Pots, pans, and baking trays. The metal must stretch significantly to form the deep bowl of a pot. 1100-O stretches perfectly without ripping.
- HVAC Heat Exchangers: Inside air conditioning units, cooling gas runs through a 1100-O aluminum pipe. The soft temper allows factories to bend the pipe into tight "U" shapes to save space inside the machine.
- Chemical Equipment: Used for non-pressure chemical storage tanks and fluid transfer lines because pure aluminum resists corrosion from many chemicals.
- Reflectors and Lighting: The surface can be highly polished to reflect light efficiently.
- Decorative Panels: Used in architecture where complex, stamped shapes are required for aesthetic purposes.
read more:https:1100-o-h14-h18-h112-aerospace-aluminum-tube
1100-O vs 1100 H14 H12 H18 tempers
This is the most common purchasing trap. Buyers often order "1100 aluminum" but forget to specify "O" or "H." What is the difference?
While "O" means fully soft (annealed), "H" means Strain Hardened (cold worked).
- 1100-O: Lowest strength, best formability. (Used for deep drawing).
- 1100-H12: Quarter-hard. Slightly stiffer, it still bends well.
- 1100-H14 aluminum tubing: Half-hard. This is the general-purpose temper. It handles physical bumps better but can only handle moderate bending.
- 1100-H18: Full-hard. Maximum strength for the 1100 series. If you try to bend an H18 pipe tightly, it will snap immediately.
Conclusion: If your factory focuses on forming, stamping, or tight bending, explicitly write "O Temper" on your purchase order.
1100-O vs 3003 and 5052 Aluminum Tubing
1100-O vs 3003 Aluminum Tubing
3003 aluminum contains manganese. It is essentially the "stronger brother" of 1100. Even in its softest O temper, a 3003 aluminum tubing is about 20% stronger than 1100-O. It still bends excellently, but it resists denting better during transport. If 1100-O feels too soft and gets damaged easily on your assembly line, upgrade to 3003.
1100-O vs 5052 Aluminum Pipe
5052 aluminum contains magnesium. It is designed for medium-to-high strength and exceptional saltwater corrosion resistance. You would use a 5052 aluminum pipe for boat fuel lines or hydraulic systems. However, 5052 is much harder to form than 1100-O. You cannot deep-draw 5052 easily without expensive heavy-duty machinery.
Can 1100-O Aluminum Be Strengthened?
The answer is No.
1100 aluminum is a non-heat-treatable alloy. It contains no magnesium or silicon, meaning heat cannot change its internal strength.
The only way to strengthen 1100-O is through cold working. Ironically, the very act of manufacturing your part (bending it, rolling it, hammering it) will naturally cause the metal to strain-harden. The corners where the metal was bent will become slightly harder and stronger than the rest of the tube.
Limitations of 1100-O Aluminum Pipe
- Zero Structural Value: Never use an 1100-O pipe for scaffolding, machine frames, brackets, or load-bearing supports. It will collapse under minimal weight.
- Low Wear Resistance: The soft surface is easily scratched, gouged, or dented during rough handling. It requires careful factory logistics.
- Not for High Pressure: Do not use this pipe for high-pressure hydraulic lines or compressed air systems. The soft pipe wall will balloon and burst.
If you need strength, you must switch to a 6000-series alloy like a 6061 pipe.
Don't let incorrect temper specifications delay your manufacturing schedule. As a direct factory supplier, we guarantee precise temper control for all our aluminum products. Request a Quote Now and get competitive pricing on bulk 1100-O aluminum tubes, sheets, and custom extrusions.
Why Choose GNEE as Your Aluminum Supplier?
At GNEE, we are a professional and globally trusted aluminum supplier. We understand the precise metallurgical needs of international manufacturers:
- Strict Temper Control: We guarantee our 1100-O aluminum is fully and uniformly annealed. No hard spots, no surprises during your bending process.
- Full Range of Tempers: Need something stiffer? We also supply fully certified 1100-H12, H14, and H18 aluminum tubing.
- Multiple Product Forms: We manufacture extruded pipes, seamless tubes, aluminum sheets, and coils tailored to your exact dimensions.
- Custom Sizes & Wall Thickness: We draw and extrude tubes to meet the tightest OD and ID tolerances for your specific machinery.
- Professional Export Packaging: Because 1100-O is extremely soft, we use rigid wooden crates, heavy interleaving materials, and secure strapping to ensure your pipes arrive 100% dent-free.
Stop fighting with inconsistent raw materials. Partner with the experts. Contact GNEE today for reliable, top-quality 1100-O aluminum solutions that keep your production running smoothly.
