When purchasing commercially pure aluminum for your manufacturing project, the choice often comes down to two highly popular grades: 1070 and 1050. Because both are typically ordered in the "O" (fully annealed) temper, they look, feel, and bend exactly the same on the factory floor.
However, making the wrong choice will either cause your product to fail quality testing or cause your purchasing department to waste money.
Here is the direct conclusion to save you time:
- 1070-O Aluminum: Has higher purity (≥99.7%). It offers the best electrical and thermal conductivity.
- 1050-O Aluminum: Has slightly lower purity (≥99.5%). It offers identical formability but at a lower material cost.
If electrical conductivity or thermal management is your top priority, choose 1070. If you are manufacturing everyday products and cost control is your main goal, choose 1050.
If you place a sheet of 1070-O next to a sheet of 1050-O, you cannot tell the difference with your bare eyes. Both have a standard silver mill finish.
More importantly, their physical state is identical. The "O" temper means both sheets have been fully annealed in a furnace. They are in their softest, most ductile state. If your workers put them into a deep drawing press or a stamping machine, both materials will behave the same-they will stretch and form smoothly without springing back or cracking.
The differences between 1070 and 1050 aluminum only become clear when you look at the microscopic chemistry and the final product performance.
Core Difference Comparison Table
| Property | 1070-O Aluminum Plate | 1050-O Aluminum Plate |
| Aluminum Content | ≥ 99.7% | ≥ 99.5% |
| Purity Level | Premium High Purity | Standard High Purity |
| Electrical Conductivity | Excellent (Top tier) | Very Good (Standard tier) |
| Mechanical Strength | Very Low | Very Low |
| Ductility (Forming) | Excellent | Excellent |
| Material Price | Higher | Lower |
| Typical Use Sector | Electrical, electronics, heat transfer | General industrial, cookware, daily hardware |
Chemical Composition of 1070-O vs 1050-O Aluminum Plate
| Element | 1070-O Aluminum (%) | 1050-O Aluminum (%) |
| Aluminum (Al) | ≥ 99.70 | ≥ 99.50 |
| Iron (Fe) | ≤ 0.25 | ≤ 0.40 |
| Silicon (Si) | ≤ 0.20 | ≤ 0.25 |
| Copper (Cu) | ≤ 0.04 | ≤ 0.05 |
Why does this matter?
In aluminum, impurities like Iron (Fe) and Silicon (Si) interrupt the flow of electricity and heat. Because 1050 aluminum allows for slightly higher levels of Iron and Silicon (up to 0.40% Fe), it cannot transmit electricity as efficiently as 1070. That 0.2% higher purity in 1070 is what you are paying a premium for.
Performance Differences of 1070-O vs 1050-O Aluminum Plate
1. Electrical & Thermal Conductivity
This is the most critical difference. 1070-O aluminum approaches 61% of the International Annealed Copper Standard (IACS) for electrical conductivity. Because it has fewer impurities, electrons and heat flow much faster through the metal.
- 1070-O: The strict choice for high-end electronics, electrical busbars, and high-efficiency heat sinks.
- 1050-O: Still highly conductive, but slightly less efficient. It can handle basic electrical shielding and general heat transfer, but it will not meet strict OEM specifications for high-voltage power transmission.
2. Formability & Deep Drawing
If you are worried about your stamping dies or deep drawing machines, relax. Because both sheets are in the fully soft "O" temper, their elongation rates are extremely high (often exceeding 35%).
Both 1070-O and 1050-O provide excellent deep drawing capabilities.
Both provide excellent bending without cracking.
Conclusion: Formability should not be your selection criteria. If forming is your only concern, buy the cheaper option.
3. Material Cost Differences
1070 aluminum requires tighter control over the raw aluminum ingot and the smelting process to guarantee the 99.7% purity. This extra quality control increases the factory production cost.
- 1070-O: More expensive. You should only pay this premium if your product absolutely requires maximum conductivity.
- 1050-O: More economical. It is the default commercial pure aluminum.
Conclusion for Buyers: The basic rule in manufacturing is: Never use 1070 if 1050 can do the job.
Quick Selection Guide for Purchasing Managers
| Your End Product / Application | Recommended Alloy | Why? |
| Electrical Busbars / Transformers | 1070-O | Needs maximum conductivity to prevent overheating. |
| Electrolytic Capacitor Base | 1070-O | Requires 99.7% purity for electrical charge storage. |
| Cookware (Pots, Pans) | 1050-O | Highly formable, food-safe, and significantly cheaper. |
| General Deep Drawn Hardware | 1050-O | Both alloys form identically; 1050 saves money. |
| Pipe Thermal Insulation Wrapping | 1050-O | 1050 reflects heat well and keeps project costs low. |
| Cost-Sensitive General Projects | 1050-O | 1050 is the ultimate economical pure aluminum. |
Common Sourcing Mistakes to Avoid
Mistake 1: Blindly ordering 1070 to "be safe."
Many buyers think higher purity means a "better" product. If you are making a cooking pot or a basic stamped metal box, the extra purity of 1070 gives you absolutely zero benefit. You are just wasting money. Buy 1050.
Mistake 2: Using 1050 for high-end electrical contacts.
If your blueprint specifies a certain electrical resistance, do not try to save money by using 1050. The higher iron and silicon content will increase resistance, causing your electrical component to overheat and fail quality control.
Mistake 3: Ignoring the "Temper" completely.
While picking between 1050 and 1070 is important, ensuring you order the "O" temper (annealed) is vital if you plan to bend or deep draw the metal. If you accidentally order 1050-H18 (hard temper), it will crack instantly in your stamping machine, regardless of the alloy.
