Temper & Tolerances

Beyond the base alloy selection, the temper—referring to the hardness and strength achieved through thermal treatment—ultimately determines the physical performance of aluminium extrusion. At ALEXCO, we offer materials in various tempers (F, T4, T5, T6) to meet specific customer needs. We surpass standard tolerances and adjust our design and manufacturing processes to align with specific design requirements.

Mill Finish Surface

T 5 Temper

Almost all our customers choose T5 temper, for its overall strength, while still being somewhat formable and bendable if required. T5 Temper is achieved by artificially ageing the material in a batch oven for several hours after extrusion

Tolerances

Standard Tolerances

At ALEXCO, our standard extrusion tolerances adhere to BS1474, the industry standard for acceptable limits on deviations in the dimensions and shape of extruded profiles. This ensures consistency and quality in manufacturing.

Powder Coating Bath

T6 Temper

T6  is available for applications requiring the maximum stiffness from the profile. T6 is achieved by ageing the material in a batch oven at higher temperatures  for several hours after extrusion.

Extrusion Lines

‘Soft’ Temper

We also supply in F (or T4) more commonly know as ‘soft’. Ideal for applications that require extensive bending and forming operations. F is less stiff and the surface noticeably less scratch resistant.

Tolerances

At ALEXCO we specialise in achieving tolerances even tighter than the standard. Understanding the customer’s requirements and the necessary tolerances is critical for us to ensure the die design is correct for your application.

Extrusion profile manufacturing tolerances vary greatly depending on the shape and size of the die, and they are often larger than people initially assume. It is important for us to understand the critical dimensions of the profile for the application, any fittings that will be clipped into or connected to the profile, and the manufacturing tolerances these components may have.

During the die design process, we will provide a drawing with the tolerances for each part of the die for your approval. Any tolerances not specifically noted will conform to BS1474.

Note: Aluminium has a coefficient of expansion of 0.000023mm per mm length of extrusion per degree Celsius. Thus, a 6m long extrusion will expand by approximately 2mm with a 15°C temperature change.

Call us today to discuss your aluminium extrusion needs with our experts.