Magnesium Alloy QE22-T6
Temper · default condition
ASTM QE22 · UNS M18220 · EN MC65210, MgRE2Ag2Zr
T6 = solution heat treated and artificially aged
The standard supply condition for all QE22A aerospace castings — maximum yield strength and creep resistance to ~200 °C.
Values for the T6 condition
Other QE22 tempers and conditions
QE22 is listed in 4 conditions; see the grade overview at QE22.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As fabricated | Rarely shipped; only for non-structural or pre-machining/HIP stock, since strength is far below T6. | 105 | 170 | 3 | 55 HB | 23 % IACS |
Solution heat treated and naturally aged | Intermediate condition used before straightening/weld repair; ductility is higher but yield strength is low — normally aged on to T6. | 115 | 220 | 6 | 60 HB | 20 % IACS |
T6DefaultThis page Solution heat treated and artificially aged | The standard supply condition for all QE22A aerospace castings — maximum yield strength and creep resistance to ~200 °C. | 200 | 260 | 3 | 80 HB | — |
hot isostatically pressed then solution treated and aged | Chosen for fracture-critical aerospace castings: HIP closes microporosity, raising ductility and fatigue life at similar yield strength. | 200 | 270 | 5 | 80 HB | 24 % IACS |
What is QE22-T6?
QE22-T6 is QE22 in the T6 temper — the standard supply condition for all QE22A aerospace castings — maximum yield strength and creep resistance to ~200 °C. QE22-T6 has a yield strength of 200 MPa (29 ksi) and a tensile strength of 260 MPa (37.7 ksi) — stronger than 88% of magnesium alloy grades. Elongation at break is 3% and the elastic modulus is 44 GPa (6.38 Msi). QE22-T6 has a density of 1.82 g/cm³ (0.0658 lb/in³), heavier than 74% of magnesium alloy grades. It melts at 549°C (1,020 °F).
Advantages
- High strength — 200 MPa (29 ksi), better than 88% of magnesium alloy grades
- Tough — resists crack growth — 16 MPa·√m (14.6 ksi·√in), better than 87% of magnesium alloy grades
- High service temperature — 200°C (392 °F), better than 84% of magnesium alloy grades
Limitations
- Limited ductility — 3%, worse than 85% of magnesium alloy grades
QE22-T6 properties
Typical room-temperature values for QE22-T6; 10 are specific to this condition. Other listed values are QE22 reference data and may not represent this condition. Bars are the position among magnesium alloy grades.
Physical3
QE22-T6 has a density of 1.82 g/cm³ (0.0658 lb/in³), heavier than 74% of magnesium alloy grades. It melts at 549°C (1,020 °F).
Mechanical14
QE22-T6 has a yield strength of 200 MPa (29 ksi) and a tensile strength of 260 MPa (37.7 ksi) — stronger than 88% of magnesium alloy grades. Elongation at break is 3% and the elastic modulus is 44 GPa (6.38 Msi).
Thermal6
QE22-T6 is rated for continuous service to 200°C (392 °F). It conducts heat at 113 W/m·K (65.3 BTU/hr·ft·°F), better than 74% of magnesium alloy grades. Thermal expansion is 26.7 µm/m·K (14.8 µin/in·°F).
Electrical3
QE22-T6 conducts electricity at 24 % IACS, better than 58% of magnesium alloy grades.
Chemical & Environmental3
Corrosion resistance is poor (28/100), better than 78% of magnesium alloy grades.
Sustainability4
Producing a kilogram of QE22-T6 takes about 380 MJ of energy and emits 32 kg of CO₂ — more than 93% of magnesium alloy grades. Typical recycled content is 15%.
Manufacturability8
QE22-T6's machinability is excellent (90/100, worse than 95% of magnesium alloy grades); weldability good (55/100); formability not recommended (10/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with QE22-T6
Is QE22 easy to machine?
Machines extremely easily with sharp positive-rake carbide tools and high speeds; use dry or mineral-oil coolant (never water-based) and keep fine chips/dust wet or inerted — Mg fines are a fire hazard.
Can QE22 be welded?
GTAW repair with matching Mg-Ag-RE or EZ33/QE22 filler under argon; preheat mildly, avoid Zr burn-off, and re-solution+age (T6) after major repair.
Can QE22 be formed, bent or molded?
Sand, investment and permanent-mold casting with SF6-free (SO2/HFC) melt cover; fluid enough for thin aerospace housings but needs good feeding and Zr grain refinement control.
What surface finishes work on QE22?
Not sulfuric-anodizable — apply chromate or chrome-free conversion (AMS 2475) or HAE/Tagnite anodic coating, then epoxy primer/topcoat; insulate from steel and aluminium fasteners to stop galvanic attack.
QE22 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 |
|---|---|---|
| Agsilver — key precipitation strengthener with Nd | 2 – 3 | 2.5 |
| REdidymium (Nd-rich rare-earth mixture) | 1.8 – 2.5 | 2.1 |
| Zrgrain refiner | 0.4 – 1 | 0.7 |
| Cuimpurity limit | ≤ 0.1 | — |
| Niimpurity limit (corrosion) | ≤ 0.01 | — |
| Siimpurity limit | ≤ 0.05 | — |
| Others (each)total others 0.30 max | ≤ 0.1 | — |
| Mg | balance | — |
QE22-T6 — frequently asked
What is QE22-T6 used for?
QE22-T6 is typically used for helicopter transmission housings, aircraft accessory gearbox casings, legacy aerospace sand and investment castings, spares for out-of-production airframes, creep-loaded engine-mounted brackets and thin-wall avionics and equipment housings. In short: creep-resistant Mg casting alloy; 200 °C service capability; legacy WE43 predecessor.
What is the yield strength of QE22-T6?
QE22-T6 has a typical yield strength of 200 MPa (29 ksi) and a tensile strength of 260 MPa (37.7 ksi) — stronger than 88% of magnesium alloy grades. Strength varies by condition: see the 4 listed tempers.
Is QE22-T6 easy to machine?
Yes — machinability is rated excellent (90/100, worse than 95% of magnesium alloy grades). Machines extremely easily with sharp positive-rake carbide tools and high speeds; use dry or mineral-oil coolant (never water-based) and keep fine chips/dust wet or inerted — Mg fines are a fire hazard.
Can QE22-T6 be welded?
Yes — weldability is rated good (55/100). GTAW repair with matching Mg-Ag-RE or EZ33/QE22 filler under argon; preheat mildly, avoid Zr burn-off, and re-solution+age (T6) after major repair.
What surface finishes work on QE22-T6?
Not sulfuric-anodizable — apply chromate or chrome-free conversion (AMS 2475) or HAE/Tagnite anodic coating, then epoxy primer/topcoat; insulate from steel and aluminium fasteners to stop galvanic attack.
Can QE22-T6 be formed, bent or molded?
Sand, investment and permanent-mold casting with SF6-free (SO2/HFC) melt cover; fluid enough for thin aerospace housings but needs good feeding and Zr grain refinement control.
What is the maximum service temperature of QE22-T6?
QE22-T6 is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between QE22-T6 and QE22-F?
T6 is the default condition — the standard supply condition for all QE22A aerospace castings — maximum yield strength and creep resistance to ~200 °C. F: rarely shipped; only for non-structural or pre-machining/HIP stock, since strength is far below T6. Yield strength is 200 MPa in T6 versus 105 MPa in F.
Sources
- ASTM B80 — Standard Specification for Magnesium-Alloy Sand Castings — ASTM International (2021)
- AMS 4418 — Magnesium Alloy Castings, 2.5Ag – 2.0RE – 0.7Zr, Solution and Precipitation Heat Treated (T6) — SAE International (2018)
- ASM Specialty Handbook: Magnesium and Magnesium Alloys — ASM International (1999)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol.13B — Corrosion: Materials (magnesium) — ASM International (2005)
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.