6xxx Series
Aluminum-Magnesium-Silicon Alloys
Overview
Good strength, excellent corrosion resistance, heat treatable, extrudable
Applications
Common Alloys
Properties
Manufacturing Process
Step 1
Material Preparation
Mg and Si additions are balanced to target Mg₂Si phase (Mg:Si = 1.73:1) for maximum precipitation hardening response.
Step 2
Melting & Alloying
Elements dissolved at 720–750 °C. Ti-B grain refiner added; rotary degasser removes hydrogen to ≤0.08 ml/100g.
Step 3
Billet Casting
DC cast into cylindrical billets sized for the extrusion press; homogenisation at 570–580 °C for 4–6 h.
Step 4
Hot Extrusion
Billets preheated to 480–530 °C and pushed through precision dies at 5–30 m/min to produce complex cross-sectional profiles.
Step 5
Solution Treatment & Quench
Exit temperature controlled so quench from the press (T5) or separate solution furnace (T6) locks Mg and Si in solid solution.
Step 6
Artificial Aging (T6)
Aged at 160–175 °C for 6–10 h; Mg₂Si precipitates deliver peak strength. Tensile, hardness, and profile dimension checks complete the process.
Step 1
Material Preparation
Mg and Si additions are balanced to target Mg₂Si phase (Mg:Si = 1.73:1) for maximum precipitation hardening response.
Step 2
Melting & Alloying
Elements dissolved at 720–750 °C. Ti-B grain refiner added; rotary degasser removes hydrogen to ≤0.08 ml/100g.
Step 3
Billet Casting
DC cast into cylindrical billets sized for the extrusion press; homogenisation at 570–580 °C for 4–6 h.
Step 4
Hot Extrusion
Billets preheated to 480–530 °C and pushed through precision dies at 5–30 m/min to produce complex cross-sectional profiles.
Step 5
Solution Treatment & Quench
Exit temperature controlled so quench from the press (T5) or separate solution furnace (T6) locks Mg and Si in solid solution.
Step 6
Artificial Aging (T6)
Aged at 160–175 °C for 6–10 h; Mg₂Si precipitates deliver peak strength. Tensile, hardness, and profile dimension checks complete the process.
Chemical Composition
EN 573-3 / AA
Max % unless range shown. Balance: Al.
| Alloy | Chem. Symbol | Si | Fe | Cu | Mn | Mg | Cr | Zn | Ti |
|---|---|---|---|---|---|---|---|---|---|
| 6061 | AlMg1SiCu | 0.40–0.80 | 0.70 | 0.15–0.40 | 0.15 | 0.80–1.2 | 0.04–0.35 | 0.25 | 0.15 |
| 6063 | AlMg0.7Si | 0.20–0.60 | 0.35 | 0.10 | 0.10 | 0.45–0.90 | 0.10 | 0.10 | 0.10 |
| 6082 | AlSi1MgMn | 0.70–1.3 | 0.50 | 0.10 | 0.40–1.0 | 0.60–1.2 | 0.25 | 0.20 | 0.10 |