Magnesium Alloy AM100A-T61
Temper
ASTM AM100A · UNS M10100
T61 = t6 variant, underaged
Use where the maximum hardness and compressive yield of AM100A are needed on thicker permanent-mold sections.
Values for the T61 condition
Other AM100A tempers and conditions
AM100A is listed in 5 conditions; see the grade overview at AM100A.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As fabricated | Lowest-cost condition for lightly loaded, dimensionally stable castings where no heat treatment is justified. | 83 | 150 | 2 | 53 HB | 68 W/m·K |
Solution heat treated and naturally aged | Pick when maximum toughness/ductility and shock resistance matter more than yield strength. | 83 | 275 | 10 | 53 HB | 66 W/m·K |
Solution heat treated and overaged (stabilized) | Choose for dimensional stability and reduced residual stress in castings that see moderate service heat or tight tolerances, trading some strength for stability. | 110 | 250 | 4 | 63 HB | — |
T6Default Solution heat treated and artificially aged | Standard supply condition: highest yield strength and hardness, accepted at the cost of very low elongation. | 152 | 275 | 1 | 69 HB | 72 W/m·K |
T61This page T6 variant, underaged | Use where the maximum hardness and compressive yield of AM100A are needed on thicker permanent-mold sections. | 160 | 275 | 1 | 74 HB | 73 W/m·K |
What is AM100A-T61?
AM100A-T61 is AM100A in the T61 temper — use where the maximum hardness and compressive yield of AM100A are needed on thicker permanent-mold sections. AM100A-T61 has a yield strength of 160 MPa (23.2 ksi) and a tensile strength of 275 MPa (39.9 ksi) — stronger than 64% of magnesium alloy grades. Elongation at break is 1% and the elastic modulus is 45 GPa (6.53 Msi). AM100A-T61 has a density of 1.81 g/cm³ (0.0654 lb/in³), heavier than 58% of magnesium alloy grades. It melts at 465°C (869 °F). T6 is the default condition FabDigit quotes; T61 is available on request or by drawing note.
Limitations
- Limited ductility — 1%, worse than 100% of magnesium alloy grades
- Hard to polish — 45/100, worse than 93% of magnesium alloy grades
- Low fracture toughness — 12 MPa·√m (10.9 ksi·√in), worse than 92% of magnesium alloy grades
- Limited service temperature — 120°C (248 °F), worse than 78% of magnesium alloy grades
- Low electrical conductivity — 12 % IACS, worse than 78% of magnesium alloy grades
AM100A-T61 properties
Typical room-temperature values for AM100A-T61; 13 are specific to this condition. Other listed values are AM100A reference data and may not represent this condition. Bars are the position among magnesium alloy grades.
Physical3
AM100A-T61 has a density of 1.81 g/cm³ (0.0654 lb/in³), heavier than 58% of magnesium alloy grades. It melts at 465°C (869 °F).
Mechanical13
AM100A-T61 has a yield strength of 160 MPa (23.2 ksi) and a tensile strength of 275 MPa (39.9 ksi) — stronger than 64% of magnesium alloy grades. Elongation at break is 1% and the elastic modulus is 45 GPa (6.53 Msi).
Thermal6
AM100A-T61 is rated for continuous service to 120°C (248 °F). It conducts heat at 73 W/m·K (42.2 BTU/hr·ft·°F), worse than 59% of magnesium alloy grades. Thermal expansion is 25.2 µm/m·K (14 µin/in·°F).
Electrical3
AM100A-T61 conducts electricity at 12 % IACS, worse than 78% of magnesium alloy grades.
Chemical & Environmental3
Corrosion resistance is poor (20/100), worse than 77% of magnesium alloy grades.
Sustainability4
Producing a kilogram of AM100A-T61 takes about 320 MJ of energy and emits 30 kg of CO₂ — less than 74% of magnesium alloy grades. Typical recycled content is 25%.
Manufacturability8
AM100A-T61's machinability is excellent (96/100, better than 87% of magnesium alloy grades); weldability good (58/100); formability not recommended (8/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with AM100A-T61
Is AM100A easy to machine?
Machines faster and with lower cutting forces than any other structural metal — use sharp tools, high speed, dry or mineral-oil cutting fluid (never water-based), and keep fine chips/dust collected wet or inert to avoid fire.
Can AM100A be welded?
GTAW/GMAW with AZ92A or AZ101A filler works well in the F condition; preheat thick sections, avoid mixing with steel spatter, and re-solution/re-age after welding T6 parts to restore properties.
Can AM100A be formed, bent or molded?
A casting alloy only — good sand and permanent-mold fluidity with SF6-free cover-gas or flux melting; not cold formable, so shape must come from the mold.
What surface finishes work on AM100A?
Always clean/pickle then apply a chromate or chrome-free conversion coat, Dow 17/HAE anodize or PEO before primer and paint; isolate all steel, brass and aluminium fasteners to prevent galvanic attack.
AM100A 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 |
|---|---|---|
| Alprincipal strengthening/ageing element (Mg17Al12) | 9.3 – 10.7 | 10 |
| Mn0.10 % min; controls Fe for corrosion | 0.1 – 0.35 | 0.15 |
| Zn | ≤ 0.3 | 0.1 |
| Si | ≤ 0.3 | — |
| Cuimpurity limit | ≤ 0.1 | — |
| Niimpurity limit | ≤ 0.01 | — |
| Fetypical high-purity practice limit; older specs control Fe via Fe/Mn ratio | ≤ 0.01 | — |
| Other (each/total)others total | ≤ 0.3 | — |
| Mg | balance | — |
AM100A-T61 — frequently asked
What is AM100A-T61 used for?
AM100A-T61 is typically used for engine covers, gearbox housings and brackets. In short: superseded by AZ91; very low cast ductility; excellent machinability, poor corrosion.
What is the yield strength of AM100A-T61?
AM100A-T61 has a typical yield strength of 160 MPa (23.2 ksi) and a tensile strength of 275 MPa (39.9 ksi) — stronger than 64% of magnesium alloy grades. Strength varies by condition: see the 5 listed tempers.
Is AM100A-T61 easy to machine?
Yes — machinability is rated excellent (96/100, better than 87% of magnesium alloy grades). Machines faster and with lower cutting forces than any other structural metal — use sharp tools, high speed, dry or mineral-oil cutting fluid (never water-based), and keep fine chips/dust collected wet or inert to avoid fire.
Can AM100A-T61 be welded?
Yes — weldability is rated good (58/100). GTAW/GMAW with AZ92A or AZ101A filler works well in the F condition; preheat thick sections, avoid mixing with steel spatter, and re-solution/re-age after welding T6 parts to restore properties.
What surface finishes work on AM100A-T61?
Always clean/pickle then apply a chromate or chrome-free conversion coat, Dow 17/HAE anodize or PEO before primer and paint; isolate all steel, brass and aluminium fasteners to prevent galvanic attack.
Can AM100A-T61 be formed, bent or molded?
A casting alloy only — good sand and permanent-mold fluidity with SF6-free cover-gas or flux melting; not cold formable, so shape must come from the mold.
What is the maximum service temperature of AM100A-T61?
AM100A-T61 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 AM100A-T6 and AM100A-F?
T6 is the default condition — standard supply condition: highest yield strength and hardness, accepted at the cost of very low elongation. F: lowest-cost condition for lightly loaded, dimensionally stable castings where no heat treatment is justified. Yield strength is 152 MPa in T6 versus 83 MPa in F.
Sources
- ASTM B199 — Magnesium-Alloy Permanent Mold Castings — ASTM International (2019)
- ASTM B80 — Magnesium-Alloy Sand Castings — ASTM International (2015)
- ASTM B93/B93M — Magnesium Alloys in Ingot Form for Sand, Permanent Mold and Die Castings — ASTM International (2020)
- ASM Specialty Handbook: Magnesium and Magnesium Alloys — ASM International (1999)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- SAE AMS 4455 / UNS M10100 designation records — SAE International (2018)
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.