Magnesium Alloy ZC63-T4
Temper
ASTM ZC63 · EN MC32110, MgZn6Cu3Mn
T4 = solution heat treated and naturally aged
Choose when maximum ductility and impact toughness matter more than yield strength.
Values for the T4 condition
Other ZC63 tempers and conditions
ZC63 is listed in 4 conditions; see the grade overview at ZC63.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As fabricated | Lowest-cost condition for lightly stressed or dimensionally critical castings where the T6 cycle cannot be tolerated. | 105 | 165 | 3 | 52 HB | 27 % IACS |
T4This page Solution heat treated and naturally aged | Choose when maximum ductility and impact toughness matter more than yield strength. | 110 | 205 | 8 | 55 HB | 25 % IACS |
T6Default Solution heat treated and artificially aged | Standard supply condition for ZC63A structural sand castings — best combination of strength, ductility and pressure tightness. | 145 | 240 | 5 | 62 HB | 122 W/m·K |
T6 | Pick for higher-volume chill castings where the finer as-cast structure lifts strength and elongation above sand-cast T6. | 150 | 250 | 6 | 65 HB | 29 % IACS |
What is ZC63-T4?
ZC63-T4 is ZC63 in the T4 temper — choose when maximum ductility and impact toughness matter more than yield strength. ZC63-T4 has a yield strength of 110 MPa (16 ksi) and a tensile strength of 205 MPa (29.7 ksi) — weaker than 83% of magnesium alloy grades. Elongation at break is 8% and the elastic modulus is 45 GPa (6.53 Msi). ZC63-T4 has a density of 1.87 g/cm³ (0.0676 lb/in³), heavier than 99% of magnesium alloy grades. It melts at 465°C (869 °F). T6 is the default condition FabDigit quotes; T4 is available on request or by drawing note.
Advantages
- Tough — resists crack growth — 16 MPa·√m (14.6 ksi·√in), better than 87% of magnesium alloy grades
Limitations
- Low strength — 110 MPa (16 ksi), worse than 83% of magnesium alloy grades
- Difficult to weld — 35/100, worse than 80% of magnesium alloy grades
- Limited service temperature — 120°C (248 °F), worse than 78% of magnesium alloy grades
ZC63-T4 properties
Typical room-temperature values for ZC63-T4; 21 are specific to this condition. Other listed values are ZC63 reference data and may not represent this condition. Bars are the position among magnesium alloy grades.
Physical3
ZC63-T4 has a density of 1.87 g/cm³ (0.0676 lb/in³), heavier than 99% of magnesium alloy grades. It melts at 465°C (869 °F).
Mechanical12
ZC63-T4 has a yield strength of 110 MPa (16 ksi) and a tensile strength of 205 MPa (29.7 ksi) — weaker than 83% of magnesium alloy grades. Elongation at break is 8% and the elastic modulus is 45 GPa (6.53 Msi).
Thermal6
ZC63-T4 is rated for continuous service to 120°C (248 °F). It conducts heat at 108 W/m·K (62.4 BTU/hr·ft·°F), better than 62% of magnesium alloy grades. Thermal expansion is 27 µm/m·K (15 µin/in·°F).
Electrical3
ZC63-T4 conducts electricity at 25 % IACS, better than 69% of magnesium alloy grades.
Chemical & Environmental3
Corrosion resistance is poor (21/100), worse than 68% of magnesium alloy grades.
Sustainability4
Producing a kilogram of ZC63-T4 takes about 320 MJ of energy and emits 33 kg of CO₂ — less than 74% of magnesium alloy grades. Typical recycled content is 20%.
Manufacturability8
ZC63-T4's machinability is excellent (93/100, worse than 78% of magnesium alloy grades); weldability fair (35/100); formability not recommended (12/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with ZC63-T4
Is ZC63 easy to machine?
Cuts extremely freely at high speed with sharp positive-rake tooling; use dry or mineral-oil coolant (never water-based) and keep fine chips/dust collected wet to avoid ignition.
Can ZC63 be welded?
TIG/GMAW with matching or EZ33-type filler is possible but Zn+Cu make the alloy hot-crack sensitive; preheat, minimise restraint and re-solution treat repairs where strength matters.
Can ZC63 be formed, bent or molded?
A casting alloy only — sand and permanent-mold with careful gating/risering for pressure tightness; grain refine and degas the melt, and protect with SF6-free cover gas.
What surface finishes work on ZC63?
Chromate or chrome-free conversion coating, HAE/plasma-electrolytic anodize or e-coat plus paint is essential; isolate from steel/aluminium fasteners to prevent galvanic attack.
ZC63 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 addition | 5.5 – 6.5 | 6 |
| Curefines interdendritic phase, improves pressure tightness; degrades corrosion | 2.4 – 3 | 2.7 |
| Mniron control / corrosion mitigation | 0.25 – 0.75 | 0.5 |
| Si | ≤ 0.2 | — |
| Fe | ≤ 0.05 | — |
| Ni | ≤ 0.01 | — |
| Others (each)max each | ≤ 0.01 | — |
| Others (total)max total | ≤ 0.3 | — |
| Mg | balance | — |
ZC63-T4 — frequently asked
What is ZC63-T4 used for?
ZC63-T4 is typically used for pump housings, structural aerospace castings and gearbox housings. In short: heat-treatable cast magnesium; good pressure tightness; machines faster than aluminium.
What is the yield strength of ZC63-T4?
ZC63-T4 has a typical yield strength of 110 MPa (16 ksi) and a tensile strength of 205 MPa (29.7 ksi) — weaker than 83% of magnesium alloy grades. Strength varies by condition: see the 4 listed tempers.
Is ZC63-T4 easy to machine?
Yes — machinability is rated excellent (93/100, worse than 78% of magnesium alloy grades). Cuts extremely freely at high speed with sharp positive-rake tooling; use dry or mineral-oil coolant (never water-based) and keep fine chips/dust collected wet to avoid ignition.
Can ZC63-T4 be welded?
With care — weldability is rated fair (35/100). TIG/GMAW with matching or EZ33-type filler is possible but Zn+Cu make the alloy hot-crack sensitive; preheat, minimise restraint and re-solution treat repairs where strength matters.
What surface finishes work on ZC63-T4?
Chromate or chrome-free conversion coating, HAE/plasma-electrolytic anodize or e-coat plus paint is essential; isolate from steel/aluminium fasteners to prevent galvanic attack.
Can ZC63-T4 be formed, bent or molded?
A casting alloy only — sand and permanent-mold with careful gating/risering for pressure tightness; grain refine and degas the melt, and protect with SF6-free cover gas.
What is the maximum service temperature of ZC63-T4?
ZC63-T4 is rated for continuous use to about 120°C (248 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between ZC63-T6 and ZC63-F?
T6 is the default condition — standard supply condition for ZC63A structural sand castings — best combination of strength, ductility and pressure tightness. F: lowest-cost condition for lightly stressed or dimensionally critical castings where the T6 cycle cannot be tolerated. Yield strength is 145 MPa in T6 versus 105 MPa in F.
Sources
- ASTM B80 — Magnesium-Alloy Sand Castings — ASTM International (2015)
- ASTM B199 — Magnesium-Alloy Permanent Mold Castings — ASTM International (2019)
- ASTM B93/B93M — Magnesium Alloys in Ingot Form for Sand Castings — 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.