Aluminum Alloy Selection Guide

Choose the right alloy for your project. Compare 1xxx through 7xxx series by strength, corrosion resistance, weldability, and cost.

Fundamentals

Understanding the Alloy Designation System

Aluminum alloys follow a standardized 4-digit numbering system. The first digit identifies the primary alloying element, which determines the alloy's core properties.

Aluminum sheet stack
Flat sheet and plate alloy forms
Aluminum round bars
Bar stock alloy selection
High-strength aluminum plate
High-strength plate alloy comparison

The International Alloy Designation System (IADS) assigns a four-digit number to every wrought aluminum alloy. The first digit defines the alloy series and its principal alloying element. This single digit tells you more about an alloy's behavior than any other specification detail.

Series Primary Alloying Element Key Property Common Alloys
1xxx None (99%+ pure aluminum) Excellent corrosion resistance, high conductivity 1060, 1100
2xxx Copper (Cu) High strength, heat treatable 2024, 2A12
3xxx Manganese (Mn) Good formability, moderate strength 3003, 3004, 3105
5xxx Magnesium (Mg) Best corrosion resistance, weldable 5052, 5083, 5754
6xxx Magnesium + Silicon (Mg-Si) Versatile, heat treatable, extrudable 6061, 6063, 6082
7xxx Zinc (Zn) Highest strength aluminum alloys 7075, 7050
Decision Tool

Quick Decision Flowchart

Answer one question to narrow down your alloy choice. Start with your most critical requirement.

Need highest corrosion resistance?
→
5xxx Series: 5052, 5083
Need heat-treatable strength?
→
6xxx (6061) or 7xxx (7075)
Need highest strength?
→
7xxx Series: 7075, 7050
Need best formability?
→
1xxx (1060, 1100) or 3xxx (3003)
Need best machinability?
→
2xxx (2024) or 7xxx (7075)
General purpose / not sure?
→
6061-T6 (Best all-rounder)
Data Reference

Complete Alloy Comparison Table

Side-by-side comparison of 10 popular aluminum alloys across mechanical, fabrication, and application properties.

Alloy Series Tensile Strength (MPa) Yield Strength (MPa) Elongation % Corrosion Weldability Formability Machinability Typical Applications Available Forms
1060 1xxx 70 30 43 Excellent Excellent Excellent Poor Chemical equipment, heat exchangers, reflectors Sheet, Plate
1100 1xxx 90 35 35 Excellent Excellent Excellent Poor Food processing, fin stock, decorative trim Sheet, Plate
3003 3xxx 110 42 30 Excellent Excellent Excellent Fair HVAC, cooking utensils, roofing, general sheet metal Sheet, Plate
5052 5xxx 230 195 12 Excellent Good Good Fair Marine hardware, fuel tanks, pressure vessels Sheet, Plate
5083 5xxx 305 215 16 Excellent Excellent Good Fair Shipbuilding, offshore platforms, cryogenic tanks Sheet, Plate
5754 5xxx 245 100 26 Excellent Excellent Excellent Fair Automotive body panels, floor panels, flooring Sheet, Plate
6061 6xxx 310 275 12 Good Good Good Good Structural, CNC machining, mold, tooling, marine fittings Sheet, Plate, Bar
6082 6xxx 340 310 10 Good Good Good Good Structural beams, bridges, transport, offshore Sheet, Plate, Bar
7050 7xxx 510 455 11 Fair Poor Poor Good Aerospace structures, bulkheads, wing skins Plate, Bar
7075 7xxx 570 505 11 Fair Poor Poor Excellent Aerospace, military, high-stress structural, mold Sheet, Plate, Bar

Values shown are typical for common tempers (H32 for 5xxx, T6/T651 for 6xxx/7xxx, O for 1xxx/3xxx). Actual values depend on specific temper and product form.

Temper System

Temper Designation Guide

The letter-number suffix after an alloy (e.g., 6061-T6) specifies how the metal was processed. This directly affects strength, hardness, and formability.

O

Annealed

Fully soft condition with maximum ductility. Used when extensive forming or bending is required before final treatment. Lowest strength state.

H1x

Strain Hardened Only

Strengthened by cold working (rolling, drawing). The second digit (2, 4, 6, 8) indicates degree of hardening: H12 = quarter-hard, H14 = half-hard, H18 = full-hard.

H2x

Strain Hardened + Partially Annealed

Cold worked beyond the desired strength, then partially annealed back. Provides better ductility than H1x at similar strength levels.

H3x

Strain Hardened + Stabilized

Cold worked then low-temperature stabilized to prevent age softening. Used for Al-Mg alloys (5xxx series) that may otherwise lose strength over time.

T3

Solution Heat Treated + Cold Worked

Solution treated at high temperature, quenched, then cold worked to improve strength. Naturally aged to a stable condition. Common for 2024-T3 aerospace sheet.

T4

Solution Heat Treated + Naturally Aged

Solution treated and quenched, then allowed to age at room temperature. Provides moderate strength with good formability for post-forming operations.

T6

Solution Heat Treated + Artificially Aged

The most common high-strength temper. Solution treated, quenched, then aged at elevated temperature (150-200C) for peak strength. Standard for 6061-T6, 7075-T6.

T651

T6 + Stress Relieved by Stretching

T6 treatment followed by controlled stretching (1-3%) to relieve internal stresses. Essential for thick plate to prevent warping during machining.

By Industry

Alloy Selection by Application

Recommended alloys for the six most common industries we serve.

⚓

Marine & Shipbuilding

Hull plating, superstructures, offshore platforms. Requires DNV/BV/ABS certification and superior saltwater resistance.

5083 5086 5052
✈

Aerospace & Aviation

Airframe structures, wing skins, bulkheads. Demands highest strength-to-weight ratio and fatigue resistance.

2024 7075 7050
🚗

Automotive

Body panels, chassis components, heat shields. Focuses on lightweight strength and good formability.

5052 5754 6061
🏧

Construction

Curtain walls, roofing, cladding, structural framing. Needs good weathering and easy fabrication.

1060 3003 6063
💻

Electronics

Heat sinks, enclosures, LED housings, bus bars. Prioritizes thermal conductivity and surface finish quality.

1060 1100 6061
📦

Packaging

Foil containers, beverage cans, blister packs. Requires food-safe grades with excellent formability.

1060 3003 8011
Common Questions

Alloy Selection FAQ

Answers to the most frequent questions our engineers receive about choosing aluminum alloys.

6061-T6 is widely considered the best general-purpose aluminum alloy. It offers a strong balance of strength (310 MPa tensile), good corrosion resistance, weldability, and machinability. It is heat treatable, available in all product forms (sheet, plate, bar, extrusion), and is the most commonly stocked alloy worldwide. If you are unsure which alloy to choose, 6061-T6 is the safest starting point.
7075 is generally considered non-weldable by conventional fusion welding methods (MIG/TIG). It is highly susceptible to hot cracking in the weld zone and suffers severe strength loss in the heat-affected zone. For applications requiring both high strength and weldability, consider 7005 or switch to 6061-T6 or 5083 depending on your strength requirements. 7075 parts are typically joined by fasteners or adhesive bonding.
H32 and T6 are two fundamentally different strengthening methods. H32 (strain hardened + stabilized) applies to non-heat-treatable alloys like 5052 and 3003 — the metal is strengthened by cold working. T6 (solution heat treated + artificially aged) applies to heat-treatable alloys like 6061 and 7075 — strength comes from precipitation hardening. You cannot apply T6 to a 5052 alloy, and you would not use H32 on a 6061 alloy.
5083-H116 is the gold standard for marine applications. Its high magnesium content provides exceptional resistance to saltwater corrosion, and the H116 temper specifically ensures resistance to exfoliation and intergranular corrosion. For less demanding marine applications (hardware, fittings), 5052-H32 is a cost-effective alternative. Avoid 2xxx and 7xxx series alloys in marine environments as they have poor corrosion resistance without protective coatings.
Choose 5052 when corrosion resistance is the top priority (marine, chemical, outdoor exposure) and you need to form the part without heat treatment. Choose 6061 when you need higher strength, better machinability, or heat-treatability for structural applications. 5052 is not heat treatable and is typically used in sheet/plate form. 6061 is available in all forms and can be heat treated to T6 for peak strength. Cost is similar; the choice depends on whether your application values corrosion resistance (5052) or structural strength and versatility (6061).

Still Not Sure Which Alloy to Choose?

Our engineers can recommend the right alloy, temper, and product form for your specific application. Get a free consultation with your quote.

Get a Free Consultation