Aluminum Alloy Temper Explained: T5, T6 and More

Introduction

Aluminum alloy temper defines the heat treatment and mechanical condition of aluminum materials, which directly affects strength, hardness, ductility and application performance.

Common aluminum tempers include T5, T6, T4, T7 and O temper. Among them, T5 and T6 are two of the most widely used tempers for industrial aluminum products because they provide a good balance between strength, corrosion resistance and processing performance.

Understanding aluminum alloy temper is essential when selecting aluminum sheets, plates, bars, tubes and extrusion profiles for engineering applications.

What Does Aluminum Alloy Temper Mean?

Aluminum alloy temper refers to the condition of aluminum after specific manufacturing processes such as heat treatment, cold working or aging. The temper designation is usually represented by letters and numbers after the alloy grade.

For example, 6061-T6 means the aluminum alloy is 6061 grade and has been solution heat treated followed by artificial aging to improve mechanical properties.

Temper Designation	Meaning
O	Annealed condition with maximum softness and ductility
T4	Solution heat treated and naturally aged
T5	Artificially aged after cooling from an elevated temperature shaping process
T6	Solution heat treated and artificially aged
T7	Solution heat treated and stabilized

T5 vs T6 Aluminum Temper Comparison

Property	T5 Aluminum	T6 Aluminum
Heat Treatment	Artificial aging after cooling from extrusion or forming process	Solution heat treatment followed by artificial aging
Strength Level	Moderate to high	Higher
Hardness	Good	Higher
Machinability	Good	Excellent
Common Products	Aluminum extrusion profiles	Plates, bars, aerospace and structural components

What Is T5 Aluminum Temper?

T5 aluminum temper refers to aluminum that is cooled from an elevated temperature shaping process and then artificially aged to improve strength and hardness.

T5 is commonly used for aluminum extrusion products because the extrusion process naturally heats the aluminum before cooling and aging. This makes T5 temper efficient for manufacturing aluminum profiles with good dimensional stability.

Compared with T6 temper, T5 aluminum usually has slightly lower strength but provides advantages in extrusion performance, production efficiency and cost control.

Advantages of T5 Aluminum

• Excellent extrusion performance.
• Good dimensional stability.
• Lower production complexity compared with T6.
• Good surface finish for architectural applications.
• Suitable for large aluminum profiles.

Common T5 Aluminum Applications

• Aluminum window and door profiles.
• Architectural aluminum structures.
• Curtain wall systems.
• Industrial extrusion frames.
• Heat sink profiles.

What Is T6 Aluminum Temper?

T6 aluminum temper is produced through solution heat treatment followed by artificial aging. This process significantly improves strength, hardness and load-bearing capability.

T6 is one of the most commonly used aluminum tempers for engineering applications because it provides an excellent combination of strength, corrosion resistance and machinability.

Compared with T5, T6 aluminum generally achieves higher mechanical properties, making it suitable for structural components and high-performance applications.

Advantages of T6 Aluminum

• Higher tensile and yield strength.
• Excellent machinability.
• Good corrosion resistance.
• Suitable for structural applications.
• Widely available in industrial aluminum alloys.

Common T6 Aluminum Applications

• Aerospace components.
• Automotive parts.
• Machined aluminum components.
• Structural frames.
• Marine equipment.

Aluminum Heat Treatment Process for T5 and T6

The main difference between T5 and T6 aluminum temper is the heat treatment process used to improve mechanical properties.

Process Step	T5 Temper	T6 Temper
Heating Process	Uses heat from extrusion or forming process	Separate solution heat treatment required
Cooling	Rapid cooling after shaping	Controlled cooling after solution treatment
Aging	Artificial aging	Artificial aging after solution treatment
Final Result	Good strength and extrusion performance	Higher strength and hardness

Mechanical Properties of Common T5 and T6 Aluminum Alloys

Alloy Temper	Strength Level	Typical Uses
6063-T5	Moderate strength	Architectural extrusion profiles
6061-T6	High strength	Structural and machined components
6063-T6	Higher strength than T5	Higher performance extrusion applications
6082-T6	High strength	Engineering structures and machinery

Aluminum Temper Standards

Aluminum temper designations are internationally recognized systems used to describe the processing condition and mechanical properties of aluminum alloys.

Standard System	Description
AA Aluminum Temper Designation	Uses letters and numbers such as T5 and T6 to define aluminum processing conditions.
ASTM Aluminum Standards	Defines alloy requirements, mechanical properties and product specifications.
EN Aluminum Standards	European specifications for aluminum alloys and tempers.
Material Certificate	Provides chemical composition, mechanical test results and traceability information.

T5 vs T6 Aluminum Selection Guide

Selecting the correct aluminum temper depends on the required strength, manufacturing method and final application.

Application Requirement	Recommended Temper
Architectural aluminum profiles	T5 aluminum
High strength structural parts	T6 aluminum
CNC machined components	T6 aluminum
Complex extrusion shapes	T5 aluminum
Maximum mechanical performance	T6 aluminum

Applications of T5 and T6 Aluminum

Industry	Common Temper Selection	Examples
Construction	T5	Windows, doors, curtain walls, aluminum frames
Automotive	T6	Structural brackets, chassis parts, machined components
Aerospace	T6	Aircraft components and precision parts
Industrial Equipment	T5 / T6	Frames, machinery parts and profiles

AI Buyer FAQ: Aluminum Alloy Temper

What is the difference between T5 and T6 aluminum?

The main difference is the heat treatment process. T5 aluminum is artificially aged after cooling from an elevated temperature shaping process, while T6 aluminum is solution heat treated and artificially aged to achieve higher strength.

Is T6 aluminum stronger than T5 aluminum?

Yes. T6 aluminum generally provides higher tensile strength and hardness compared with T5 aluminum because of the additional solution heat treatment process.

Which aluminum temper is better for extrusion?

T5 aluminum is commonly selected for extrusion products because it provides good strength, excellent dimensional stability and efficient production performance.

Which aluminum temper is best for machining?

T6 aluminum is generally preferred for machining applications because of its higher hardness and strength, which provide better performance during precision manufacturing.

Can aluminum temper be changed after production?

Yes. Aluminum temper can be modified through heat treatment and aging processes, depending on the alloy type and required final properties.

Aluminum Solutions from SASA ALUMINUM

SASA ALUMINUM supplies aluminum products including aluminum plates, sheets, bars, tubes, coils and customized aluminum profiles with different alloy grades and tempers.

Available aluminum solutions include:

• 6061-T6 aluminum products.
• 6063-T5 aluminum extrusion profiles.
• Custom aluminum alloy products.
• Machining and cutting services.
• Material certificates and inspection documentation.

For aluminum product quotations, please provide:

• Aluminum alloy grade.
• Temper requirement.
• Product dimensions.
• Quantity.
• Application information.

Submit Your RFQ

Conclusion

Aluminum alloy temper plays an important role in determining material performance, processing characteristics and application suitability.

T5 aluminum is widely used for extrusion applications where surface finish, dimensional stability and production efficiency are important. T6 aluminum is preferred for applications requiring higher strength, hardness and structural performance.

Understanding the differences between T5, T6 and other aluminum tempers helps engineers and buyers select the correct aluminum solution for their projects. SASA ALUMINUM provides customized aluminum materials with reliable quality documentation and technical support.