Aluminum EN AC-51200
EN AC-51200
EN AC-51200 (AlMg9, 520.0/ZL301) is the highest-magnesium alloy of the EN 1706 Al-Mg casting series, non-heat-treatable in F and solution-treated in T4, and it offers the highest strength and toughness of that group together with excellent corrosion resistance (score 78).
Reference datasheet — EN AC-51200 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the F condition
EN AC-51200 tempers and conditions
EN AC-51200 is supplied in 2 conditions, soft to hard. F is the default FabDigit quotes; the values on this page are for it.
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
FDefault As fabricated | Standard EN 1706 delivery condition for AlMg9 chill castings — good corrosion resistance and machinability with no heat treatment. | 150 | 230 | 2 | 70 HB | 21 % IACS |
Solution heat treated and naturally aged | Pick when maximum strength plus very high ductility/toughness and best corrosion resistance are needed (equivalent to 520.0-T4 / ZL301-T4); long ~18–24 h solution soak near 430 °C is required. | 175 | 310 | 12 | 75 HB | 21 % IACS |
What is EN AC-51200?
EN AC-51200 (AlMg9, 520.0/ZL301) is the highest-magnesium alloy of the EN 1706 Al-Mg casting series, non-heat-treatable in F and solution-treated in T4, and it offers the highest strength and toughness of that group together with excellent corrosion resistance (score 78). It is used for marine and aerospace fittings and for polished or anodized decorative castings, at 230 MPa tensile, 150 MPa yield, 2% elongation, 70 HB and 87 W/m·K. The trade-offs are difficult foundry practice, a 100 °C service limit and sensitivity to grain-boundary sensitization; EN AC-51300 AlMg5 is easier to cast when its lower strength is acceptable. EN AC-51200 has a density of 2.6 g/cm³ (0.0939 lb/in³), lighter than 97% of aluminum grades. It melts at 450°C (842 °F). EN AC-51200 has a yield strength of 150 MPa (21.8 ksi) and a tensile strength of 230 MPa (33.4 ksi) — weaker than 65% of aluminum grades. Elongation at break is 2% and the elastic modulus is 68 GPa (9.86 Msi).
What is EN AC-51200 used for?
- marine hardware
- aerospace fittings
- decorative/architectural castings
Advantages
- Good corrosion resistance — 78/100, better than 94% of aluminum grades
- Polishes to a fine finish — 80/100, better than 93% of aluminum grades
- Easy to machine — 78/100, better than 89% of aluminum grades
Limitations
- Poor heat conductor — 87 W/m·K (50.3 BTU/hr·ft·°F), worse than 100% of aluminum grades
- Low electrical conductivity — 21 % IACS, worse than 99% of aluminum grades
- Limited service temperature — 100°C (212 °F), worse than 91% of aluminum grades
- Limited ductility — 2%, worse than 87% of aluminum grades
EN AC-51200 properties
Typical room-temperature values for EN AC-51200-F; bars are the position among aluminum grades.
Physical3
EN AC-51200 has a density of 2.6 g/cm³ (0.0939 lb/in³), lighter than 97% of aluminum grades. It melts at 450°C (842 °F).
Mechanical10
EN AC-51200 has a yield strength of 150 MPa (21.8 ksi) and a tensile strength of 230 MPa (33.4 ksi) — weaker than 65% of aluminum grades. Elongation at break is 2% and the elastic modulus is 68 GPa (9.86 Msi).
Thermal6
EN AC-51200 is rated for continuous service to 100°C (212 °F). It conducts heat at 87 W/m·K (50.3 BTU/hr·ft·°F), worse than 100% of aluminum grades. Thermal expansion is 25 µm/m·K (13.9 µin/in·°F).
Electrical3
EN AC-51200 conducts electricity at 21 % IACS, worse than 99% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is very good (78/100), better than 94% of aluminum grades.
Sustainability4
Producing a kilogram of EN AC-51200 takes about 200 MJ of energy and emits 12.5 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 40%.
Manufacturability8
EN AC-51200's machinability is very good (78/100, better than 89% of aluminum grades); weldability good (55/100); formability poor (20/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the aluminum family
Yield strength against density for every aluminum grade FabDigit runs. EN AC-51200 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with EN AC-51200
Is EN AC-51200 easy to machine?
Machines very freely with sharp high-rake carbide/PCD tools and generous coolant; gives short chips and an excellent finish, better than Al-Si castings.
Can EN AC-51200 be welded?
TIG/MIG weldable with 5356 or matching Al-Mg filler under strict oxide removal and low heat input; avoid preheat/soaking that sensitizes grain boundaries.
Can EN AC-51200 be formed, bent or molded?
Difficult to cast: melt oxidizes and picks up hydrogen readily, requiring protective flux/cover gas, Be-free modern melt protection, chilled feeding and generous risers to control hot tearing and shrinkage.
EN AC-51200 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 |
|---|---|---|
| Mgprincipal alloying element | 8 – 10.5 | 9 |
| Siimpurity limit per EN 1706; kept <0.3 in 520.0/ZL301 | ≤ 2.5 | |
| Fe | ≤ 0.55 | |
| Cu | ≤ 0.1 | |
| Mn | ≤ 0.55 | |
| Zn | ≤ 0.25 | |
| Tigrain refiner | ≤ 0.2 | |
| Others (each) | ≤ 0.05 | |
| Others (total) | ≤ 0.15 | |
| Al | balance |
What surface finishes work on EN AC-51200?
Excellent bright/clear anodizing and polishing response; chromate-free conversion coats and paints adhere well — plating is rarely used.
Surface treatments FabDigit runs on aluminum parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Equivalent designations
Standards and trade names that resolve to Aluminum EN AC-51200 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
How much does EN AC-51200 cost?
EN AC-51200 is a standard-cost aluminum ($$), cheaper than about 71% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
EN AC-51200 — frequently asked
What is EN AC-51200 used for?
EN AC-51200 is typically used for marine hardware, aerospace fittings and decorative/architectural castings. In short: strongest Al-Mg casting alloy; excellent seawater resistance; demanding foundry practice.
What is the yield strength of EN AC-51200?
EN AC-51200 has a typical yield strength of 150 MPa (21.8 ksi) and a tensile strength of 230 MPa (33.4 ksi) — weaker than 65% of aluminum grades. Strength varies by condition: see the 2 listed tempers.
Is EN AC-51200 easy to machine?
Yes — machinability is rated very good (78/100, better than 89% of aluminum grades). Machines very freely with sharp high-rake carbide/PCD tools and generous coolant; gives short chips and an excellent finish, better than Al-Si castings.
Can EN AC-51200 be welded?
Yes — weldability is rated good (55/100). TIG/MIG weldable with 5356 or matching Al-Mg filler under strict oxide removal and low heat input; avoid preheat/soaking that sensitizes grain boundaries.
What surface finishes work on EN AC-51200?
Excellent bright/clear anodizing and polishing response; chromate-free conversion coats and paints adhere well — plating is rarely used.
Can EN AC-51200 be formed, bent or molded?
Difficult to cast: melt oxidizes and picks up hydrogen readily, requiring protective flux/cover gas, Be-free modern melt protection, chilled feeding and generous risers to control hot tearing and shrinkage.
What is the maximum service temperature of EN AC-51200?
EN AC-51200 is rated for continuous use to about 100°C (212 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between EN AC-51200-F and EN AC-51200-T4?
F is the default condition — standard EN 1706 delivery condition for AlMg9 chill castings — good corrosion resistance and machinability with no heat treatment. T4: pick when maximum strength plus very high ductility/toughness and best corrosion resistance are needed (equivalent to 520.0-T4 / ZL301-T4); long ~18–24 h solution soak near 430 °C is required. Yield strength is 150 MPa in F versus 175 MPa in T4.
How much does EN AC-51200 cost?
EN AC-51200 is a standard-cost aluminum ($$), cheaper than about 71% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- EN 1706 — Aluminium and aluminium alloys: castings, chemical composition and mechanical properties — CEN (2020)
- GB/T 1173 (ZL301 / ZAlMg10) — SAC (2013)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys (520.0) — ASM International (1990)
- ASM Handbook Vol.15 — Casting — ASM International (2008)
- Aluminum Association Pink Sheets — Designations and Chemical Composition Limits for Aluminum Alloys in the Form of Castings and Ingot — The Aluminum Association (2018)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.