6061 vs 7075 Aluminium: Strength, Cost & Uses (2025 Guide)

Major Alloying Elements

• 6061: Magnesium + Silicon — Good strength, weldable, corrosion resistant
• 7075: Zinc + Magnesium + Copper — Extremely high strength, aerospace-grade

Summary:

• 6061 is balanced and versatile
• 7075 contains copper & zinc → higher strength but lower corrosion resistance

Key Conclusion: 7075 is almost twice as strong as 6061, making it a top choice for aerospace & defense.

• 6061 Machinability: Easy to machine, clean chips, low tool wear, ideal for CNC machining
• 7075 Machinability: Good, but higher hardness causes tool wear; requires carbide tooling

Winner → 6061

• 6061: Excellent weldability, used in structures & fabrication
• 7075: Very difficult to weld, prone to cracking, loses strength near weld zones

Winner → 6061 by a large margin

6061: Excellent corrosion resistance, ideal for marine environments

7075: Lower corrosion resistance, vulnerable to stress corrosion cracking, needs anodizing in harsh conditions

Winner → 6061

Both alloys have the same density: 2.70 g/cm³.

But the strength-to-weight ratio is higher for 7075.

• 6061: Lower cost — common, easy to produce
• 7075: Higher cost — aerospace-grade, premium alloy

If budget matters → choose 6061.

• Structural frames
• Marine parts
• Automotive components
• Bicycle frames
• Machinery parts
• Heat exchangers
• CNC machined components

• Aircraft fittings
• Aerospace components
• Motorsport components
• High-performance gears
• Defense equipment
• High-strength bolts & fasteners
• Precision robotics

Choose 6061 if:

• You need a general-purpose alloy
• Weldability is important
• Corrosion resistance is essential
• Budget matters
• You are making structural or marine components

Choose 7075 if:

• You need maximum strength
• The application involves extreme loads
• It is for aerospace, motorsport, or defense
• Fatigue resistance is critical
• Weight reduction + strength are priorities

Both 6061 and 7075 aluminium alloys are engineering powerhouses — but for different reasons. 6061 offers excellent weldability, corrosion resistance, and overall versatility, making it ideal for general engineering and structural applications.

7075, on the other hand, delivers exceptional strength and fatigue resistance, making it suitable for aerospace, motorsport, and high-performance components.