Magnesium Alloy ZM1
ZM1 is a high-strength Mg-Zn-Zr sand casting alloy comparable to ZK51A, with zirconium grain refinement and no rare-earth or aluminium content; F and T1 conditions are on file.
Reference datasheet — ZM1 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 T1 condition
ZM1 tempers and conditions
ZM1 is supplied in 2 conditions, soft to hard. T1 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 |
|---|---|---|---|---|---|---|
As fabricated | Use for low-stress housings where the aging cycle is not worth the cost; strength ~15 % below T1. | 140 | 235 | 6 | 60 HB | 26 % IACS |
T1Default Cooled from hot working and naturally aged | Standard supply condition for ZM1: age ~175 °C/16 h for peak yield strength with useful ductility. | 165 | 275 | 8 | 70 HB | 117 W/m·K |
What is ZM1?
ZM1 is a high-strength Mg-Zn-Zr sand casting alloy comparable to ZK51A, with zirconium grain refinement and no rare-earth or aluminium content; F and T1 conditions are on file. It delivers 165 MPa yield, 275 MPa tensile, 8% elongation and 70 HB with 117 W/m·K conductivity, a machinability score of 95 and a service limit of 150 °C, higher than the Mg-Al-Zn casting grades. The weldability score of 30 reflects strong hot-crack sensitivity, so TIG is used only for minor defect repair, and the alloy needs conversion coating plus paint for corrosion protection. ZM5 (AZ91-type) is the easier-to-cast, weldable alternative at lower strength. ZM1 has a density of 1.81 g/cm³ (0.0654 lb/in³), heavier than 58% of magnesium alloy grades. It melts at 550°C (1,022 °F). ZM1 has a yield strength of 165 MPa (23.9 ksi) and a tensile strength of 275 MPa (39.9 ksi) — stronger than 67% of magnesium alloy grades. Elongation at break is 8% and the elastic modulus is 45 GPa (6.53 Msi).
What is ZM1 used for?
- aerospace fittings
- high-strength cast brackets
- instrument housings
Advantages
- High electrical conductivity — 28 % IACS, better than 85% of magnesium alloy grades
- Conducts heat well — 117 W/m·K (67.6 BTU/hr·ft·°F), better than 80% of magnesium alloy grades
Limitations
- High embodied carbon — 35 kg CO₂/kg, worse than 91% of magnesium alloy grades
- Difficult to weld — 30/100, worse than 90% of magnesium alloy grades
ZM1 properties
Typical room-temperature values for ZM1-T1; bars are the position among magnesium alloy grades.
Physical3
ZM1 has a density of 1.81 g/cm³ (0.0654 lb/in³), heavier than 58% of magnesium alloy grades. It melts at 550°C (1,022 °F).
Mechanical13
ZM1 has a yield strength of 165 MPa (23.9 ksi) and a tensile strength of 275 MPa (39.9 ksi) — stronger than 67% of magnesium alloy grades. Elongation at break is 8% and the elastic modulus is 45 GPa (6.53 Msi).
Thermal6
ZM1 is rated for continuous service to 150°C (302 °F). It conducts heat at 117 W/m·K (67.6 BTU/hr·ft·°F), better than 80% of magnesium alloy grades. Thermal expansion is 27.1 µm/m·K (15.1 µin/in·°F).
Electrical3
ZM1 conducts electricity at 28 % IACS, better than 85% of magnesium alloy grades.
Chemical & Environmental3
Corrosion resistance is poor (18/100), worse than 88% of magnesium alloy grades.
Sustainability4
Producing a kilogram of ZM1 takes about 300 MJ of energy and emits 35 kg of CO₂ — less than 92% of magnesium alloy grades. Typical recycled content is 25%.
Manufacturability8
ZM1's machinability is excellent (95/100, better than 54% of magnesium alloy grades); weldability poor (30/100); 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.
Strength versus weight in the magnesium alloy family
Yield strength against density for every magnesium alloy grade FabDigit runs. ZM1 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with ZM1
Is ZM1 easy to machine?
Cuts very freely at high speed with sharp positive-rake tools and low forces; keep chips coarse and dry/mineral-oil cooled — fine dry chips are a fire hazard, never use water-based coolant floods on grinding dust.
Can ZM1 be welded?
Zn-rich Mg-Zn-Zr alloys are hot-crack sensitive; TIG repair with EZ33A/ZK-type filler and preheat 260–320 °C only for minor casting defects, avoid structural weld joints.
Can ZM1 be formed, bent or molded?
Sand or permanent-mould casting with SF6-free (SO2/HFC) melt protection and sulphur/boron-inhibited sand; Zr addition needs an Al- and Si-free melt and settling to keep grain refinement effective.
ZM1 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 |
|---|---|---|
| Znprincipal strengthener | 3.5 – 5.5 | 4.5 |
| Zrgrain refiner (soluble Zr) | 0.5 – 1 | 0.7 |
| Siimpurity max | ≤ 0.05 | |
| Feimpurity max | ≤ 0.05 | |
| Cuimpurity max | ≤ 0.1 | |
| Niimpurity max, corrosion critical | ≤ 0.01 | |
| Alimpurity max (Al poisons Zr refinement) | ≤ 0.05 | |
| Other, totaltotal impurities | ≤ 0.3 | |
| Mg | balance |
What surface finishes work on ZM1?
Pickle then chromate/fluoride conversion (Dow 7/17) or HAE/PEO anodic coating followed by epoxy primer + topcoat; isolate all steel and CFRP fasteners to prevent galvanic attack.
Equivalent designations
Standards and trade names that resolve to Magnesium Alloy ZM1 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Similar grades
- ZK51A
How much does ZM1 cost?
ZM1 is a premium-cost magnesium alloy ($$$), cheaper than about 51% 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.
ZM1 — frequently asked
What is ZM1 used for?
ZM1 is typically used for aerospace fittings, high-strength cast brackets and instrument housings. In short: high-strength Mg-Zn-Zr casting; 150 °C service ceiling; hot-crack sensitive, avoid welding.
What is the yield strength of ZM1?
ZM1 has a typical yield strength of 165 MPa (23.9 ksi) and a tensile strength of 275 MPa (39.9 ksi) — stronger than 67% of magnesium alloy grades. Strength varies by condition: see the 2 listed tempers.
Is ZM1 easy to machine?
Yes — machinability is rated excellent (95/100, better than 54% of magnesium alloy grades). Cuts very freely at high speed with sharp positive-rake tools and low forces; keep chips coarse and dry/mineral-oil cooled — fine dry chips are a fire hazard, never use water-based coolant floods on grinding dust.
Can ZM1 be welded?
Not readily — weldability is rated poor (30/100). Zn-rich Mg-Zn-Zr alloys are hot-crack sensitive; TIG repair with EZ33A/ZK-type filler and preheat 260–320 °C only for minor casting defects, avoid structural weld joints.
What surface finishes work on ZM1?
Pickle then chromate/fluoride conversion (Dow 7/17) or HAE/PEO anodic coating followed by epoxy primer + topcoat; isolate all steel and CFRP fasteners to prevent galvanic attack.
Can ZM1 be formed, bent or molded?
Sand or permanent-mould casting with SF6-free (SO2/HFC) melt protection and sulphur/boron-inhibited sand; Zr addition needs an Al- and Si-free melt and settling to keep grain refinement effective.
What is the maximum service temperature of ZM1?
ZM1 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 ZM1-T1 and ZM1-F?
T1 is the default condition — standard supply condition for ZM1: age ~175 °C/16 h for peak yield strength with useful ductility. F: use for low-stress housings where the aging cycle is not worth the cost; strength ~15 % below T1. Yield strength is 165 MPa in T1 versus 140 MPa in F.
How much does ZM1 cost?
ZM1 is a premium-cost magnesium alloy ($$$), cheaper than about 51% 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
- ASTM B80 Standard Specification for Magnesium-Alloy Sand Castings (ZK51A) — ASTM International (2020)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASM Specialty Handbook: Magnesium and Magnesium Alloys — ASM International (1999)
- ASM Handbook Vol.15 — Casting — ASM International (2008)
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.