What is aluminum forging? What are its types?

Understanding aluminum forging¹ can be complex, leading to choosing the wrong manufacturing process for your needs. This can impact component strength and cost. It's a key process for creating strong, lightweight parts.

Aluminum forging is a manufacturing process where aluminum alloy is heated and shaped using localized compressive forces, like hammering or pressing. Its main types are open-die forging for large, simpler shapes, closed-die (impression-die) forging for more complex parts, and rolled ring forging for seamless rings.

At SWA Forging, this process is at the heart of what we do. We specialize in creating high-quality, large-diameter forged rings and discs for various industries. Forging aluminum enhances its mechanical properties, making it an ideal choice for applications requiring high strength and reliability. Understanding the nuances of forging and its different types is crucial for our clients, whether they are traders or machining companies.

What is the best aluminum for forging?

Choosing the wrong aluminum alloy for forging can result in parts that don't meet strength requirements or are difficult to manufacture. Selecting an alloy with good forgeability and the right final properties is essential.

The best aluminum alloys for forging typically include the 2xxx (e.g., 2014, 2618), 6xxx (e.g., 6061), and 7xxx series (e.g., 7075, 7050, 7049). These offer excellent strength, toughness, and respond well to the forging process and subsequent heat treatment.

When we talk about the "best" aluminum for forging at SWA Forging, it really depends on the specific application's demands. However, certain alloys consistently stand out due to their inherent characteristics.
Good forging alloys need a combination of:

• Ductility and Malleability: The ability to be deformed under compressive stress without cracking. This is crucial for the alloy to flow and fill the die cavity or be shaped effectively.
• Strength Potential: The ability to achieve high strength through the forging process and subsequent heat treatment. The grain refinement that occurs during forging contributes significantly to this.
• Response to Heat Treatment: Many high-strength forgings rely on heat-treatable alloys where the desired mechanical properties are developed after forging.

Here are some commonly used and highly regarded forging alloys:

• 2xxx Series (Aluminum-Copper alloys): Alloys like 2014 and 2618 are known for their very high strength, especially at elevated temperatures (for 2618). They are often used in aerospace and high-performance automotive applications. 2014 is a go-to for structural components requiring high strength-to-weight ratios.
• 6xxx Series (Aluminum-Magnesium-Silicon alloys): 6061 is perhaps the most versatile and widely used forging alloy. It offers a great balance of good strength, excellent corrosion resistance, good weldability, and good forgeability. We produce many forged rings and discs from 6061.
• 7xxx Series (Aluminum-Zinc alloys): This series contains some of the highest-strength aluminum alloys available. 7075 is a classic example, widely used in aerospace structures for its exceptional strength. 7050 offers improved stress corrosion cracking resistance and toughness compared to 7075, making it suitable for thick sections. 7049 is another high-strength option.

Choosing the right alloy is a critical first step, and we often guide our clients through this selection process.

Which is lighter 6061 or 7075 aluminum?

Confused about whether 6061 or 7075 aluminum is lighter for your project? Misunderstanding this can lead to incorrect weight calculations or material choices. Surprisingly, their densities are very similar.

6061 aluminum and 7075 aluminum have virtually the same density, meaning a solid piece of each with the identical volume will have almost identical weight. 7075 is negligibly denser (about 4% more) than 6061.

This is a common question, and the answer often surprises people. The "lightness" of a material is determined by its density – mass per unit volume.

• The density of 6061 aluminum is approximately 2.70 grams per cubic centimeter (g/cm³) or 0.0975 pounds per cubic inch (lb/in³).
• The density of 7075 aluminum is approximately 2.81 grams per cubic centimeter (g/cm³) or 0.101 pounds per cubic inch (lb/in³).

As you can see, 7075 aluminum² is ever so slightly denser than 6061 aluminum³. For most practical purposes in terms of raw material weight for a given volume, this difference is negligible. If you had two identical solid cubes, one of 6061 and one of 7075, the 7075 cube would be about 4% heavier.

However, the confusion often arises because 7075 is significantly stronger than 6061. This means that for an application requiring a certain level of strength, you might be able to use less 7075 material (e.g., a thinner profile or a smaller part) to achieve the same structural performance as a larger or thicker 6061 part. In such a scenario, the final component made from 7075 could indeed be lighter than the functionally equivalent 6061 component, not because the material itself is less dense, but because its higher strength allows for a more weight-efficient design. This is leveraging its superior strength-to-weight ratio. So, while the material density is similar, 7075's higher strength allows for the design of lighter parts for the same load-bearing capacity.

What is the strongest type of aluminum?

Searching for the absolute strongest aluminum alloy for a demanding application? Using an inadequately strong alloy can lead to failure. Certain alloys, especially in the 7xxx series, offer the highest strength.

The strongest types of aluminum alloys commercially available are typically found in the 7xxx series, with alloys like 7075, 7050, and notably 7068 being among the leaders in terms of tensile and yield strength, especially in their optimal tempers (e.g., T6, T651, T7x).

When we talk about the "strongest" aluminum, we're usually referring to its ultimate tensile strength (the maximum stress it can withstand while being stretched or pulled before necking) and yield strength (the stress at which it begins to deform permanently). Several aluminum alloys are renowned for their exceptional strength, often comparable to some steels but at about a third of the weight.

Here are some of the contenders for the "strongest" title:

• 7075 Aluminum: Often considered the workhorse of high-strength aluminum alloys, especially in the T6 temper. It offers excellent strength-to-weight ratio and is widely used in aerospace, military applications, and high-performance sporting goods. Typical ultimate tensile strength for 7075-T6 can be around 572 MPa (83,000 psi).
• 7050 Aluminum: Developed as an improvement over 7075, particularly for thicker sections, offering better toughness and resistance to stress corrosion cracking while maintaining high strength. Common in aircraft structural components.
• 7068 Aluminum: This is one of the strongest commercially available aluminum alloys. In tempers like T6511, it can achieve ultimate tensile strengths exceeding 690 MPa (100,000 psi), which is significantly higher than many other aluminum alloys. It's used in applications where maximum strength is critical, like connecting rods or high-stress ordnance components.
• 2024 Aluminum: An older but still very relevant high-strength alloy from the 2xxx series, known for its good fatigue resistance. Often used in aircraft structures.

It's crucial to remember that the temper of the alloy plays a massive role in its final strength. For example, 7075 in an annealed ('O') state is much softer and weaker than 7075-T6. The heat treatment process is what develops these high strength levels. At SWA Forging, we ensure our forged products meet the specified temper and strength requirements through precise control of our forging and heat treatment processes.

While these are the "strongest," the best choice always depends on a balance of properties including toughness, corrosion resistance, cost, and manufacturability for the intended application.

Is 6061 aluminum forged?

Considering 6061 aluminum for a project and wondering if it's suitable for forging? Using an alloy not well-suited for forging can lead to manufacturing difficulties or suboptimal part performance. Yes, 6061 aluminum is very commonly and effectively forged.

Yes, 6061 aluminum is one of the most popular and widely used aluminum alloys for forging. Its excellent combination of good strength, corrosion resistance, machinability, and forgeability makes it a versatile choice for many applications.

At SWA Forging, 6061 aluminum is a staple material for many of the forged rings and discs we produce. Its popularity for forging stems from a fantastic balance of properties that make it suitable for a wide array of applications.
Here's why 6061 is so well-suited for forging:

• Good Forgeability: 6061 flows well under the heat and pressure of the forging process, allowing it to fill die cavities and achieve complex shapes with good grain structure refinement.
• Excellent Corrosion Resistance: This makes forged 6061 parts suitable for outdoor and marine applications where they might be exposed to moisture and other corrosive elements.
• Good Strength and Toughness: After forging and subsequent heat treatment (typically to a T6 temper), 6061 develops good mechanical strength and toughness, making it robust enough for many structural and mechanical components. While not as strong as the 7xxx series, its strength is more than adequate for a vast range of uses.
• Weldability: 6061 is readily weldable, which can be an advantage if the forged component needs to be integrated into a larger assembly.
• Machinability: In its T6 temper, 6061 machines well, which is important for our clients who perform secondary machining operations on our forged blanks.
• Cost-Effectiveness: Compared to some of the higher-strength aerospace alloys, 6061 is generally more economical.

Common applications for forged 6061 aluminum include automotive parts (wheels, suspension components), bicycle frames, scuba tanks, fishing reels, valves, and various structural and machinery components. The forging process enhances its properties compared to cast or extruded 6061, providing a finer grain structure and improved fatigue life. This is why our customers often specify forged 6061 for their critical applications.

Conclusion

Aluminum forging creates strong, lightweight parts, with open-die, closed-die, and ring rolling as key types. Alloys like 6061 and 7075 are excellent choices, offering distinct strength benefits.