Optimized Heat Treatment Process for Special aluminum alloy Shaft Sleeves

The shaft sleeve is a key functional component in gear pump systems.

It is installed at both ends of the high-speed gear to support bearings and ensure stable rotation.

Its mechanical performance directly affects the service life and reliability of the pump.

To meet demanding operating conditions, a special aluminum alloy shaft sleeve with enhanced strength and wear resistance is required.

This article introduces an optimized heat treatment process that significantly improves performance while reducing production cost.

Functional Requirements of Aluminum Alloy Shaft Sleeves

Shaft sleeves operate under high load and continuous friction.

They must provide sufficient strength, good toughness, and excellent wear resistance.

Conventional Aluminum Alloys often struggle to meet these combined requirements.

For this reason, a non-standard aluminum-tin alloy system is adopted.

Role of Alloying Elements

Copper is added to strengthen the aluminum matrix.

It improves hardness and contributes to overall mechanical stability.

Tin forms a soft Al-Sn eutectic structure.

This eutectic phase enhances wear resistance and reduces friction during operation.

The balance between strength and wear resistance is achieved through precise alloy design.

Limitations of the Traditional Heat Treatment Process

The original heat treatment process consisted of solution treatment at 515℃ for 6 hours.

This was followed by water quenching and aging at 180℃ for 8 hours with air cooling.

Microstructural Defects

The Al-Sn eutectic has a low melting point of approximately 229℃.

Heating the alloy to 515℃ causes eutectic overburning.

During quenching, remelted pellets form at grain boundaries.

This leads to oxidation, microscopic voids, and reduced grain strength.

These defects significantly increase the risk of early failure in service.

Low Production Efficiency

The total heat treatment time reaches 16 hours.

This results in low production efficiency and high energy consumption.

Such a process is unsuitable for large-scale industrial manufacturing.

Development of an Improved Heat Treatment Process

Through metallographic observation and mechanical testing, a new process was developed.

The optimized treatment uses a single-stage process of 250℃ for 7 hours with air cooling.

Microstructure Optimization

At 250℃, the Al-Sn eutectic distributes along grain boundaries in a broken network.

This structure ensures uniform wear resistance.

At the same time, the aluminum matrix is not divided by continuous eutectic phases.

This improves plasticity and toughness.

Hardness and Strength Improvement

The alloy contains a relatively low copper content.

Fast cooling during metal mold casting ensures copper remains in solid solution.

This provides a natural quenching effect.

Subsequent natural aging further increases hardness.

Test results show that tensile strength increases by 47% compared with the traditional process.

Industrial Validation and Production Results

Based on process testing, a trial production of 400 shaft sleeves was conducted.

All products passed hardness testing, metallographic inspection, and bench testing.

The process was officially adopted for mass production.

Since implementation, hundreds of thousands of shaft sleeves have been produced with stable quality.

Production efficiency increased by 1.3 times.

Annual cost savings include approximately 70,000 yuan and over 80,000 kW·h of electricity.

Why Choose saivs Aluminum Alloy Shaft Sleeves

SAIVS applies optimized heat treatment technology to aluminum alloy shaft sleeves.

Strict process control ensures consistent microstructure and mechanical performance.

Stable wear resistance and enhanced tensile strength reduce equipment downtime.

This provides long-term value for industrial users.

Choosing a reliable manufacturer ensures both product quality and operational efficiency.

Conclusion

Heat treatment optimization plays a critical role in aluminum alloy shaft sleeve performance.

The 250℃×7h air cooling process offers superior strength, wear resistance, and efficiency.

This proven process supports large-scale production with reduced energy consumption.

Advanced manufacturing solutions contribute directly to pump reliability and service life.