High-Strength 6061 T651 Aluminum Plate Explained

What is 6061 T651 Aluminum Plate?  

The 6061 T651 aluminum plate is a specially treated aluminum alloy material. “6061” denotes the alloy type, “T6” refers to the heat treatment process, and “T651” indicates an additional pre-stretching process applied after T6 treatment. This combination enhances the mechanical properties of the material.  

From a technical perspective, the elastic modulus of this alloy is 68.9 GPa (10.0×10⁶ psi) in tension and 69.7 GPa (10.1×10⁶ psi) in compression. In terms of hardness, it measures 30 HB in the O condition, while the T6 and T651 states achieve 95 HB, demonstrating significantly improved hardness.  

Understanding the T651 Process  

In the designation of this aluminum plate:  

– “T” stands for Thermal Treated  

– “6” signifies solution heat treatment followed by artificial aging  

– “51” represents the additional pre-stretching process  

The T651 process involves pre-stretching and artificial aging after the standard T6 treatment. With a deformation rate of 1.5–3% (for thin and medium plates), internal stresses are effectively eliminated. This treatment reduces distortion during subsequent machining, greatly improving product quality and production efficiency.  

Differences Between T651 and T6 Aluminum Plates  

While the T6 variant undergoes solution heat treatment followed directly by artificial aging, the T651 version includes pre-stretching before aging. Key distinctions include:  

1. Internal Stress: T6 retains higher residual stress, making it more prone to deformation during machining.  
2. Dimensional Stability: T651 is better suited for precision applications, minimizing elastic recovery-induced dimensional changes.  
3. Applications: T6 is suitable for less critical dimensions, whereas T651 is recommended for precision components.  

Composition of 6061 Alloy  

The primary alloying elements in 6061 aluminum are magnesium and silicon, forming Mg₂Si phases. Other additives and their roles include:  

– Manganese and chromium: Counteract iron’s adverse effects.  

– Trace copper or zinc: Enhance strength without significantly compromising corrosion resistance.  

– Copper: Mitigates negative impacts of titanium and iron on conductivity.  

– Zirconium or titanium: Refine grain structure and control recrystallization.  

– Lead and bismuth: Improve machinability.  

This balanced composition ensures optimal strength, corrosion resistance, and workability.  

Alternative Product Options  

In addition to the 6061 T651 variant, we offer various alloy plates, including aluminum checker plates—a popular choice for their anti-slip properties and aesthetic appeal. We provide tailored material solutions for diverse applications.  

Whether for architectural decoration, transportation, or precision machinery, this high-performance aluminum plate delivers reliable stability and superior processing characteristics to meet demanding requirements.