Aluminium ENAW-AlMg0.7Si Pipes & Tube(EU EN, DIN, WNR)

Product Description

The designation EN AW-AlMg0.7Si (often referred to simply as AlMg0.7Si) is the European standardized chemical name for the material registered as EN AW-6063. Under the German system, it carries the Werkstoffnummer WNr 3.32206.

When ordered as pipes or tubes, this alloy represents the global industry standard for applications requiring high-quality surface finishes, complex cross-sections, and excellent corrosion resistance.

Technical Standard Breakdown

When sourcing this material in Europe or to European technical specifications, it is governed by a unified system:

• Prefix Meaning: EN (European Norm), AW (Aluminium Wrought alloy).

• Chemical Family: AlMg0.7Si indicates it belongs to the 6000-series, alloyed primarily with Magnesium ($\approx 0.7\%$) and Silicon to allow for thermal precipitation hardening.

• Standard Integration: EN AW-6063 / AlMg0.7Si fully replaces the historical German DIN 1725-1 standard designation (AlMgSi0.5).

Delivery and Tolerances (EN Standards)

Unlike flat-rolled sheets or plates, extruded and drawn aluminum pipes/tubes are manufactured and verified against specific European standards that dictate dimensional limits, straightness, and eccentricity:

• EN 755-2: Defines the mechanical property limits for extruded bars, tubes, and profiles.

• EN 755-7: Governs dimensions and shape tolerances specifically for seamless extruded tubes.

• EN 755-8: Governs dimensions and shape tolerances for porthole/structural extruded tubes.

• EN 12020-2: Applies to high-precision extruded profiles and tubes where tolerances must be exceptionally tight for matching or sliding assemblies.

Mechanical Properties by Temper (EN 755-2)

The mechanical performance of EN AW-AlMg0.7Si tubing varies dramatically based on its heat-treatment delivery state. The two most prominent structural tempers are T4 and T6:

Manufacturing Distinctions: Seamless vs. Porthole Pipes

When reviewing technical datasheets for AlMg0.7Si tubes, the manufacturing method dictates pressure performance:

1. Seamless Pipes (Die/Mandrel Extrusion)

• Process: Extruded from a hollow billet over a mandrel, or pierced during processing. The metal never splits during forming.

• Characteristics: No internal weld lines.

• Use Case: Crucial for high-pressure fluid lines, critical gas transport, or components subjected to intense severe bending, flare testing, or dynamic cyclic loads.

2. Porthole / Structural Tubes (Bridge Die Extrusion)

• Process: Solid aluminum billets are pressed through a bridge die where the stream splits around a core and fuses back together under immense pressure and heat inside the die.

• Characteristics: Contains longitudinal solid-state weld lines that are nearly invisible to the naked eye.

• Use Case: Ideal for architectural trims, structural framing, railings, furniture, and low-pressure conduit where absolute pressure containment is not required.

Fabrication, Anodizing, & Coating

• Cold Workability: In the T4 state, the material is highly ductile and can be bent into tight radii or flared easily. In the T6 state, heavy bending may crack the outer fibers of the tube wall.

• Anodizing Class: It is graded as AQC (Anodizing Quality Quality) compatible. It anodizes beautifully to produce uniform matte, satin, or bright clear finishes, as well as electrolytic coloring (bronze, black).

• Machining: While easily cut, drilled, and tapped, it produces long, gummy chips compared to high-machining alloys like 2011 or 6082. High speeds and proper lubrication are recommended.