Magnesium Alloy ZK30-T5
Temper
ASTM ZK30 · EN MgZn3Zr · ISO ISO-WD32250
T5 = cooled from hot working and artificially aged
Choose when a 10–20 % strength gain over as-extruded is needed without a separate solution treatment; slightly lower ductility.
Values for the T5 condition
Other ZK30 tempers and conditions
ZK30 is listed in 3 conditions; see the grade overview at ZK30.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
FDefault As fabricated | Standard stock condition for ZK30 bar, profile and tube; best ductility and lowest cost. | 195 | 275 | 13 | 58 HB | 28 % IACS |
T5This page Cooled from hot working and artificially aged | Choose when a 10–20 % strength gain over as-extruded is needed without a separate solution treatment; slightly lower ductility. | 230 | 300 | 10 | 68 HB | 29 % IACS |
Solution heat treated and artificially aged | Occasional special-order condition for maximum and most uniform strength in heavy sections; rarely stocked for ZK30. | 250 | 315 | 10 | 72 HB | — |
What is ZK30-T5?
ZK30-T5 is ZK30 in the T5 temper — choose when a 10–20 % strength gain over as-extruded is needed without a separate solution treatment; slightly lower ductility. ZK30-T5 has a yield strength of 230 MPa (33.4 ksi) and a tensile strength of 300 MPa (43.5 ksi) — stronger than 93% of magnesium alloy grades. Elongation at break is 10% and the elastic modulus is 45 GPa (6.53 Msi). ZK30-T5 has a density of 1.8 g/cm³ (0.065 lb/in³), lighter than 63% of magnesium alloy grades. It melts at 535°C (995 °F). F is the default condition FabDigit quotes; T5 is available on request or by drawing note.
Advantages
- High strength — 230 MPa (33.4 ksi), better than 93% of magnesium alloy grades
- Conducts heat well — 125 W/m·K (72.2 BTU/hr·ft·°F), better than 91% of magnesium alloy grades
- High electrical conductivity — 29 % IACS, better than 91% of magnesium alloy grades
- Forms and bends easily — 28/100, better than 79% of magnesium alloy grades
Limitations
- Difficult to weld — 28/100, worse than 96% of magnesium alloy grades
- High embodied carbon — 35 kg CO₂/kg, worse than 91% of magnesium alloy grades
ZK30-T5 properties
Typical room-temperature values for ZK30-T5; 35 are specific to this condition. Other listed values are ZK30 reference data and may not represent this condition. Bars are the position among magnesium alloy grades.
Physical3
ZK30-T5 has a density of 1.8 g/cm³ (0.065 lb/in³), lighter than 63% of magnesium alloy grades. It melts at 535°C (995 °F).
Mechanical14
ZK30-T5 has a yield strength of 230 MPa (33.4 ksi) and a tensile strength of 300 MPa (43.5 ksi) — stronger than 93% of magnesium alloy grades. Elongation at break is 10% and the elastic modulus is 45 GPa (6.53 Msi).
Thermal6
ZK30-T5 is rated for continuous service to 130°C (266 °F). It conducts heat at 125 W/m·K (72.2 BTU/hr·ft·°F), better than 91% of magnesium alloy grades. Thermal expansion is 26.5 µm/m·K (14.7 µin/in·°F).
Electrical3
ZK30-T5 conducts electricity at 29 % IACS, better than 91% of magnesium alloy grades.
Chemical & Environmental3
Corrosion resistance is poor (25/100), better than 64% of magnesium alloy grades.
Sustainability4
Producing a kilogram of ZK30-T5 takes about 335 MJ of energy and emits 35 kg of CO₂ — more than 54% of magnesium alloy grades. Typical recycled content is 25%.
Manufacturability8
ZK30-T5's machinability is excellent (95/100, better than 54% of magnesium alloy grades); weldability poor (28/100); formability poor (28/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with ZK30-T5
Is ZK30 easy to machine?
Machines faster than any aluminium — high speeds, sharp positive-rake tools, dry or with mineral oil; never use water-based coolant on fine chips and keep swarf collected to avoid fire risk.
Can ZK30 be welded?
GTAW/GMAW possible in inert gas but Zn-Zr composition is hot-crack sensitive; use matching Mg-Zn-Zr or EZ33-type filler, preheat and low restraint, and prefer friction-stir or mechanical joining for structural parts.
Can ZK30 be formed, bent or molded?
Extrudes readily at 300–400 °C with finer grain than ZK60; cold formability is poor — bend, deep draw or roll form warm (200–300 °C) with generous radii.
What surface finishes work on ZK30?
Not sulfuric-anodizable; apply chrome-free conversion coating, HAE/Dow 17 or plasma electrolytic oxidation plus epoxy sealing, and always isolate from steel/copper/CFRP fasteners to prevent galvanic attack.
ZK30 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 strengthening element | 2.5 – 4 | 3 |
| Zrgrain refiner | 0.45 – 0.8 | 0.6 |
| Alimpurity limit | ≤ 0.05 | — |
| Mnimpurity limit | ≤ 0.1 | — |
| Siimpurity limit | ≤ 0.05 | — |
| Cuimpurity limit | ≤ 0.05 | — |
| Feimpurity limit; controls corrosion rate | ≤ 0.05 | — |
| Niimpurity limit; controls corrosion rate | ≤ 0.01 | — |
| Mg | balance | — |
ZK30-T5 — frequently asked
What is ZK30-T5 used for?
ZK30-T5 is typically used for extruded rod and bar stock, moderate-strength structural extrusions, machined lightweight brackets from bar, extruded frame profiles for portable equipment, sporting-goods tubing and weight-critical instrument housings. In short: fine-grain Zr-refined extrusion alloy; lower-strength ZK60 alternative; poor weldability, high machinability.
What is the yield strength of ZK30-T5?
ZK30-T5 has a typical yield strength of 230 MPa (33.4 ksi) and a tensile strength of 300 MPa (43.5 ksi) — stronger than 93% of magnesium alloy grades. Strength varies by condition: see the 3 listed tempers.
Is ZK30-T5 easy to machine?
Yes — machinability is rated excellent (95/100, better than 54% of magnesium alloy grades). Machines faster than any aluminium — high speeds, sharp positive-rake tools, dry or with mineral oil; never use water-based coolant on fine chips and keep swarf collected to avoid fire risk.
Can ZK30-T5 be welded?
Not readily — weldability is rated poor (28/100). GTAW/GMAW possible in inert gas but Zn-Zr composition is hot-crack sensitive; use matching Mg-Zn-Zr or EZ33-type filler, preheat and low restraint, and prefer friction-stir or mechanical joining for structural parts.
What surface finishes work on ZK30-T5?
Not sulfuric-anodizable; apply chrome-free conversion coating, HAE/Dow 17 or plasma electrolytic oxidation plus epoxy sealing, and always isolate from steel/copper/CFRP fasteners to prevent galvanic attack.
Can ZK30-T5 be formed, bent or molded?
Extrudes readily at 300–400 °C with finer grain than ZK60; cold formability is poor — bend, deep draw or roll form warm (200–300 °C) with generous radii.
What is the maximum service temperature of ZK30-T5?
ZK30-T5 is rated for continuous use to about 130°C (266 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between ZK30-F and ZK30-T6?
F is the default condition — standard stock condition for ZK30 bar, profile and tube; best ductility and lowest cost. T6: occasional special-order condition for maximum and most uniform strength in heavy sections; rarely stocked for ZK30. Yield strength is 195 MPa in F versus 250 MPa in T6.
Sources
- ISO 3116 — Magnesium and magnesium alloys: wrought magnesium alloys — ISO (2019)
- ASTM B107/B107M — Magnesium-Alloy Extruded Bars, Rods, Profiles, Tubes and Wire — ASTM International (2021)
- ASM Specialty Handbook: Magnesium and Magnesium Alloys — ASM International (1999)
- 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.