Magnesium Alloy EV31A · finish state · default condition
Magnesium Alloy EV31A As Cast
Properties of the As Cast condition, compared with the other EV31A tempers.
Untreated foundry condition, used only for non-structural parts or as the starting point before T6 solution treatment and ageing.
What is EV31A As Cast?
EV31A As Cast is EV31A supplied in the As Cast condition — untreated foundry condition, used only for non-structural parts or as the starting point before T6 solution treatment and ageing. EV31A As Cast has a yield strength of 110 MPa (16 ksi) and a tensile strength of 195 MPa (28.3 ksi) — weaker than 83% of magnesium alloy grades. Elongation at break is 4% and the elastic modulus is 44 GPa (6.38 Msi). EV31A As Cast has a density of 1.82 g/cm³ (0.0658 lb/in³), heavier than 74% of magnesium alloy grades. It melts at 545°C (1,013 °F).
Advantages
- Good corrosion resistance — 32/100, better than 96% of magnesium alloy grades
- Tough — resists crack growth — 17 MPa·√m (15.5 ksi·√in), better than 93% of magnesium alloy grades
Limitations
- High embodied carbon — 42 kg CO₂/kg, worse than 99% of magnesium alloy grades
- Low electrical conductivity — 11 % IACS, worse than 98% of magnesium alloy grades
- Low strength — 110 MPa (16 ksi), worse than 83% of magnesium alloy grades
EV31A As Cast properties
Typical room-temperature values for EV31A As Cast — 7 properties are specific to this condition; the rest are grade-level values shared by every EV31A temper. Each bar shows where the value sits among the magnesium alloy grades in FabDigit's library — further right is higher.
Physical3
EV31A As Cast has a density of 1.82 g/cm³ (0.0658 lb/in³), heavier than 74% of magnesium alloy grades. It melts at 545°C (1,013 °F).
Mechanical14
EV31A As Cast has a yield strength of 110 MPa (16 ksi) and a tensile strength of 195 MPa (28.3 ksi) — weaker than 83% of magnesium alloy grades. Elongation at break is 4% and the elastic modulus is 44 GPa (6.38 Msi).
Thermal6
EV31A As Cast is rated for continuous service to 150°C (302 °F). It conducts heat at 110 W/m·K (63.6 BTU/hr·ft·°F), better than 65% of magnesium alloy grades. Thermal expansion is 26.7 µm/m·K (14.8 µin/in·°F).
Electrical3
EV31A As Cast conducts electricity at 11 % IACS, worse than 98% of magnesium alloy grades.
Chemical & Environmental3
Corrosion resistance is poor (32/100), better than 96% of magnesium alloy grades.
Sustainability4
Producing a kilogram of EV31A As Cast takes about 400 MJ of energy and emits 42 kg of CO₂ — more than 98% of magnesium alloy grades. Typical recycled content is 15%.
Manufacturability8
EV31A As Cast's machinability is excellent (90/100, worse than 95% of magnesium alloy grades); weldability very good (72/100); formability poor (15/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other EV31A tempers and conditions
EV31A is also supplied in 1 other condition. The full side-by-side table is on the EV31A overview.
- As CastDefaultUntreated foundry condition, used only for non-structural parts or as the starting point before T6 solution treatment and ageing.110 MPa yield · 55 HB
- T6Standard supply and design condition for aerospace EV31A castings (AMS 4429 / ASTM B80) — best combination of room- and elevated-temperature strength.172 MPa yield · 70 HB
Working with EV31A As Cast
Is EV31A easy to machine?
Machines very easily with sharp carbide tools, high speeds and generous rake; use dry or mineral-oil coolant (never water-based) and manage fine chips to avoid ignition.
Can EV31A be welded?
TIG/GTAW repair-weldable with matching EV31A filler under argon; solution/ageing (T6) should be re-applied or a local post-weld age used to restore properties.
Can EV31A be formed, bent or molded?
Sand, investment and permanent-mould casting alloy with good fluidity and low hot-tearing tendency; use protective cover gas (SF6-free alternatives) and 0.6–1.0 % Zr grain refinement — not a wrought/formable alloy.
What surface finishes work on EV31A?
Apply chromate-free conversion coat plus epoxy primer/topcoat, or plasma-electrolytic (Keronite/Tagnite) coating; insulate all joints to steel or carbon fibre to prevent galvanic attack.
EV31A 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 |
|---|---|---|
| Ndprincipal RE strengthener | 2.6 – 3.1 | 2.85 |
| Gdheavy RE for elevated-temperature stability | 1 – 1.7 | 1.3 |
| Zn | 0.2 – 0.5 | 0.35 |
| Zrgrain refiner | 0.4 – 1 | 0.6 |
| Feimpurity limit | ≤ 0.01 | — |
| Cuimpurity limit | ≤ 0.03 | — |
| Niimpurity limit | ≤ 0.01 | — |
| Siimpurity limit | ≤ 0.01 | — |
| Others (each)total others 0.30 max | ≤ 0.01 | — |
| Mg | balance | — |
EV31A As Cast — frequently asked
What is EV31A As Cast used for?
EV31A As Cast is typically used for aircraft engine casings, helicopter transmission housings, motorsport gearbox castings, auxiliary gearbox covers, pump and actuator bodies and structural aerospace sand castings. In short: high-temp powertrain magnesium.
What is the yield strength of EV31A As Cast?
EV31A As Cast has a typical yield strength of 110 MPa (16 ksi) and a tensile strength of 195 MPa (28.3 ksi) — weaker than 83% of magnesium alloy grades. Strength varies by condition: see the 2 listed tempers.
Is EV31A As Cast easy to machine?
Yes — machinability is rated excellent (90/100, worse than 95% of magnesium alloy grades). Machines very easily with sharp carbide tools, high speeds and generous rake; use dry or mineral-oil coolant (never water-based) and manage fine chips to avoid ignition.
Can EV31A As Cast be welded?
Yes — weldability is rated very good (72/100). TIG/GTAW repair-weldable with matching EV31A filler under argon; solution/ageing (T6) should be re-applied or a local post-weld age used to restore properties.
What surface finishes work on EV31A As Cast?
Apply chromate-free conversion coat plus epoxy primer/topcoat, or plasma-electrolytic (Keronite/Tagnite) coating; insulate all joints to steel or carbon fibre to prevent galvanic attack.
Can EV31A As Cast be formed, bent or molded?
Sand, investment and permanent-mould casting alloy with good fluidity and low hot-tearing tendency; use protective cover gas (SF6-free alternatives) and 0.6–1.0 % Zr grain refinement — not a wrought/formable alloy.
What is the maximum service temperature of EV31A As Cast?
EV31A As Cast is rated for continuous use to about 150°C (302 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between EV31A As Cast and EV31A-T6?
As Cast is the default condition — untreated foundry condition, used only for non-structural parts or as the starting point before T6 solution treatment and ageing. T6: standard supply and design condition for aerospace EV31A castings (AMS 4429 / ASTM B80) — best combination of room- and elevated-temperature strength. Yield strength is 110 MPa in As Cast versus 172 MPa in T6.
Can FabDigit make parts in EV31A As Cast?
Yes — EV31A As Cast is available for CNC machining with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- Elektron 21 (EV31A) alloy datasheet — Magnesium Elektron / Luxfer MEL Technologies (2020)
- AMS 4429 — Magnesium Alloy Castings, EV31A-T6 — SAE International (2018)
- ASTM B80 — Standard Specification for Magnesium-Alloy Sand Castings — ASTM (2020)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
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.