Magnesium Alloy AZ63A-T6
Temper · default condition
ASTM AZ63A · UNS M11630
T6 = solution heat treated and artificially aged
Standard structural condition: best combination of tensile/yield strength and hardness for legacy AZ63A castings.
Values for the T6 condition
Other AZ63A tempers and conditions
AZ63A is listed in 4 conditions; see the grade overview at AZ63A.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As fabricated | Lowest-cost condition for non-critical or lightly loaded legacy castings; no heat treatment cost or distortion. | 95 | 200 | 6 | 50 HB | 79 W/m·K |
Solution heat treated and naturally aged | Choose when maximum toughness/ductility and shock resistance are needed at moderate yield strength. | 95 | 275 | 12 | 55 HB | 72 W/m·K |
Cooled from hot working and artificially aged | Cheap ageing-only treatment: modest yield-strength and dimensional-stability gain without solution-treatment distortion. | 105 | 200 | 4 | 55 HB | 79 W/m·K |
T6DefaultThis page Solution heat treated and artificially aged | Standard structural condition: best combination of tensile/yield strength and hardness for legacy AZ63A castings. | 130 | 275 | 5 | 73 HB | 76 W/m·K |
What is AZ63A-T6?
AZ63A-T6 is AZ63A in the T6 temper — standard structural condition: best combination of tensile/yield strength and hardness for legacy AZ63A castings. AZ63A-T6 has a yield strength of 130 MPa (18.9 ksi) and a tensile strength of 275 MPa (39.9 ksi) — weaker than 71% of magnesium alloy grades. Elongation at break is 5% and the elastic modulus is 45 GPa (6.53 Msi). AZ63A-T6 has a density of 1.84 g/cm³ (0.0665 lb/in³), heavier than 89% of magnesium alloy grades. It melts at 455°C (851 °F).
Limitations
- Low fracture toughness — 12 MPa·√m (10.9 ksi·√in), worse than 92% of magnesium alloy grades
- Limited service temperature — 120°C (248 °F), worse than 78% of magnesium alloy grades
AZ63A-T6 properties
Typical room-temperature values for AZ63A-T6; 14 are specific to this condition. Other listed values are AZ63A reference data and may not represent this condition. Bars are the position among magnesium alloy grades.
Physical3
AZ63A-T6 has a density of 1.84 g/cm³ (0.0665 lb/in³), heavier than 89% of magnesium alloy grades. It melts at 455°C (851 °F).
Mechanical13
AZ63A-T6 has a yield strength of 130 MPa (18.9 ksi) and a tensile strength of 275 MPa (39.9 ksi) — weaker than 71% of magnesium alloy grades. Elongation at break is 5% and the elastic modulus is 45 GPa (6.53 Msi).
Thermal6
AZ63A-T6 is rated for continuous service to 120°C (248 °F). It conducts heat at 76 W/m·K (43.9 BTU/hr·ft·°F), worse than 59% of magnesium alloy grades. Thermal expansion is 26 µm/m·K (14.4 µin/in·°F).
Electrical3
AZ63A-T6 conducts electricity at 14 % IACS, worse than 58% of magnesium alloy grades.
Chemical & Environmental3
Corrosion resistance is poor (22/100), worse than 57% of magnesium alloy grades.
Sustainability4
Producing a kilogram of AZ63A-T6 takes about 330 MJ of energy and emits 27 kg of CO₂ — less than 56% of magnesium alloy grades. Typical recycled content is 30%.
Manufacturability8
AZ63A-T6's machinability is excellent (95/100, better than 54% of magnesium alloy grades); weldability good (65/100); formability poor (15/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with AZ63A-T6
Is AZ63A easy to machine?
Outstanding machinability — high speeds, sharp positive-rake tools, minimal cutting force; keep chips dry and never use water-based coolant near fine swarf (fire risk).
Can AZ63A be welded?
GTAW/GMAW with AZ92A or AZ61A filler in argon; preheat thick sections and re-solution/re-age T4/T6 castings after welding to restore properties.
Can AZ63A be formed, bent or molded?
Sand and permanent-mold casting alloy with good fluidity but needs SF6-free cover gas/flux protection and generous risering; not suitable for cold forming.
What surface finishes work on AZ63A?
Always chromate/fluoride conversion coat (ASTM D1732) or apply Dow 17/HAE/PEO anodic coating, then epoxy prime and paint; insulate all steel and copper fasteners to avoid galvanic attack.
AZ63A chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Al | 5.3 – 6.7 | 6 |
| Zn | 2.5 – 3.5 | 3 |
| MnMn controls Fe tolerance / corrosion | 0.15 – 0.6 | 0.25 |
| Si | ≤ 0.3 | — |
| Cu | ≤ 0.25 | — |
| Nimax — strongly degrades corrosion | ≤ 0.01 | — |
| Femax, high-purity practice | ≤ 0.01 | — |
| Others (each/total)0.30 total | ≤ 0.3 | — |
| Mg | balance | — |
AZ63A-T6 — frequently asked
What is AZ63A-T6 used for?
AZ63A-T6 is typically used for sand-cast housings and gearcases, legacy aerospace and industrial castings, permanent-mould covers and brackets, instrument and equipment frames, replacement castings for obsolete assemblies and sacrificial anode and cathodic-protection components. In short: heat-treatable magnesium casting; legacy alternative to AZ91; best-welding Mg casting alloy.
What is the yield strength of AZ63A-T6?
AZ63A-T6 has a typical yield strength of 130 MPa (18.9 ksi) and a tensile strength of 275 MPa (39.9 ksi) — weaker than 71% of magnesium alloy grades. Strength varies by condition: see the 4 listed tempers.
Is AZ63A-T6 easy to machine?
Yes — machinability is rated excellent (95/100, better than 54% of magnesium alloy grades). Outstanding machinability — high speeds, sharp positive-rake tools, minimal cutting force; keep chips dry and never use water-based coolant near fine swarf (fire risk).
Can AZ63A-T6 be welded?
Yes — weldability is rated good (65/100). GTAW/GMAW with AZ92A or AZ61A filler in argon; preheat thick sections and re-solution/re-age T4/T6 castings after welding to restore properties.
What surface finishes work on AZ63A-T6?
Always chromate/fluoride conversion coat (ASTM D1732) or apply Dow 17/HAE/PEO anodic coating, then epoxy prime and paint; insulate all steel and copper fasteners to avoid galvanic attack.
Can AZ63A-T6 be formed, bent or molded?
Sand and permanent-mold casting alloy with good fluidity but needs SF6-free cover gas/flux protection and generous risering; not suitable for cold forming.
What is the maximum service temperature of AZ63A-T6?
AZ63A-T6 is rated for continuous use to about 120°C (248 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between AZ63A-T6 and AZ63A-F?
T6 is the default condition — standard structural condition: best combination of tensile/yield strength and hardness for legacy AZ63A castings. F: lowest-cost condition for non-critical or lightly loaded legacy castings; no heat treatment cost or distortion. Yield strength is 130 MPa in T6 versus 95 MPa in F.
Sources
- ASTM B80 — Magnesium-Alloy Sand Castings — ASTM International (2015)
- ASTM B93/B93M — Magnesium Alloys in Ingot Form for Sand, Permanent Mold and Die Castings — ASTM International (2020)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys (Magnesium castings) — ASM International (1990)
- ASM Specialty Handbook: Magnesium and Magnesium Alloys — ASM International (1999)
- ASTM D1732 / ASTM B893 — Conversion and anodic coatings on magnesium — ASTM International (2019)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.