Aluminium Alloy Grades — 5052, 6061, 6063, 7075 Comparison

Introduction

Aluminium alloys are organized by a four-digit numbering system where the first digit indicates the primary alloying element. The four most commonly used wrought aluminium alloys in industry — 5052, 6061, 6063, and 7075 — each have distinct properties that make them ideal for specific applications.

This guide provides a side-by-side comparison to help you select the right aluminium grade for your project.

Series Classification

5xxx Series (Aluminium-Magnesium):

•Primary alloying element: Magnesium

•Best corrosion resistance (especially marine)

•Not heat-treatable — strengthened by work hardening

•Example: 5052

6xxx Series (Aluminium-Magnesium-Silicon):

•Primary alloying elements: Magnesium + Silicon

•Good balance of strength, formability, and corrosion resistance

•Heat-treatable (T4, T6 tempers)

•Examples: 6061, 6063

7xxx Series (Aluminium-Zinc):

•Primary alloying element: Zinc

•Highest strength of all aluminium alloys

•Heat-treatable

•Moderate corrosion resistance

•Example: 7075

Properties Comparison

Property	5052-H32	6061-T6	6063-T6	7075-T6
Tensile Strength (MPa)	228	310	241	572
Yield Strength (MPa)	193	276	214	503
Elongation (%)	12	12	12	11
Hardness (Brinell)	60	95	73	150
Density (g/cm³)	2.68	2.70	2.69	2.81
Machinability	Fair	Good	Fair	Good
Weldability	Excellent	Good	Excellent	Poor
Corrosion Resistance	Excellent	Good	Good	Fair
Cost	Low	Medium	Low-Medium	High

Applications

Aluminium 5052:

•Marine hulls and structures

•Fuel tanks and chemical vessels

•Road signs and traffic equipment

•Hydraulic tubes

•Home appliances

•Best choice for marine and saltwater exposure

Aluminium 6061 (Most Versatile):

•Aerospace structures

•Automotive frames and wheels

•Bicycle frames

•Bridge railings and walkways

•Screw machine products

•General structural applications

Aluminium 6063 (Architectural Grade):

•Window and door frames

•Architectural trim and panels

•Furniture and store fixtures

•Electrical conduit and pipe railings

•Irrigation pipes

•Best surface finish of all aluminium alloys

Aluminium 7075 (Aerospace Grade):

•Aircraft structural components (wings, fuselage)

•Military equipment

•Rock climbing equipment

•Competitive cycling parts

•Mould tooling for plastics

•Highest strength-to-weight ratio

How to Choose the Right Grade

Choose 5052 when:

•Marine/saltwater environment

•Excellent weldability is needed

•Moderate strength is sufficient

•Forming and bending is required

Choose 6061 when:

•High strength + good machinability needed

•Structural applications requiring heat treatment

•General-purpose engineering applications

•Good corrosion resistance + strength balance

Choose 6063 when:

•Surface finish and appearance matter

•Complex extrusion profiles needed

•Architectural and decorative applications

•Anodizing will be applied

Choose 7075 when:

•Maximum strength is required

•Weight savings are critical (aerospace)

•Stress-critical structural components

•Cost and weldability are secondary concerns

Starlight Tubes supplies aluminium pipes, sheets, and bars in all four grades. Contact us for specifications and pricing.

Frequently Asked Questions

Q.Which aluminium alloy is strongest?

Aluminium 7075-T6 is the strongest common aluminium alloy with a tensile strength of 572 MPa and yield strength of 503 MPa. It is used primarily in aerospace and military applications where the highest strength-to-weight ratio is required.

Q.Which aluminium grade is best for marine use?

Aluminium 5052 is the best choice for marine and saltwater environments. It has the highest corrosion resistance among common aluminium alloys, excellent weldability, and good formability. It is widely used for boat hulls, marine hardware, and fuel tanks.