Magnesium Alloy AZ61B · temper
Magnesium Alloy AZ61B-T5
Properties of the T5 condition, compared with the other AZ61B tempers.
Pick when a modest yield-strength gain over F is needed on heavy extrusions, accepting lower elongation.
What is AZ61B-T5?
AZ61B-T5 is AZ61B in the T5 temper — pick when a modest yield-strength gain over F is needed on heavy extrusions, accepting lower elongation. AZ61B-T5 has a yield strength of 250 MPa (36.3 ksi) and a tensile strength of 320 MPa (46.4 ksi) — stronger than 97% of magnesium alloy grades. Elongation at break is 12% and the elastic modulus is 45 GPa (6.53 Msi). AZ61B-T5 has a density of 1.8 g/cm³ (0.065 lb/in³), lighter than 63% of magnesium alloy grades. It melts at 510°C (950 °F). F is the default condition FabDigit quotes; T5 is available on request or by drawing note.
Advantages
- Tough — resists crack growth — 20 MPa·√m (18.2 ksi·√in), better than 100% of magnesium alloy grades
- High strength — 250 MPa (36.3 ksi), better than 97% of magnesium alloy grades
Limitations
- Limited service temperature — 120°C (248 °F), worse than 78% of magnesium alloy grades
AZ61B-T5 properties
Typical room-temperature values for AZ61B-T5 — 9 properties are specific to this condition; the rest are grade-level values shared by every AZ61B temper. Each bar shows where the value sits among the magnesium alloy grades in FabDigit's library — further right is higher.
Physical3
AZ61B-T5 has a density of 1.8 g/cm³ (0.065 lb/in³), lighter than 63% of magnesium alloy grades. It melts at 510°C (950 °F).
Mechanical13
AZ61B-T5 has a yield strength of 250 MPa (36.3 ksi) and a tensile strength of 320 MPa (46.4 ksi) — stronger than 97% of magnesium alloy grades. Elongation at break is 12% and the elastic modulus is 45 GPa (6.53 Msi).
Thermal6
AZ61B-T5 is rated for continuous service to 120°C (248 °F). It conducts heat at 80 W/m·K (46.2 BTU/hr·ft·°F), worse than 56% of magnesium alloy grades. Thermal expansion is 26 µm/m·K (14.4 µin/in·°F).
Electrical3
AZ61B-T5 conducts electricity at 13.8 % IACS, worse than 61% of magnesium alloy grades.
Chemical & Environmental3
Corrosion resistance is poor (22/100), worse than 57% of magnesium alloy grades.
Sustainability4
Producing a kilogram of AZ61B-T5 takes about 350 MJ of energy and emits 30 kg of CO₂ — more than 74% of magnesium alloy grades. Typical recycled content is 25%.
Manufacturability8
AZ61B-T5's machinability is excellent (95/100, better than 54% of magnesium alloy grades); weldability very good (70/100); formability poor (20/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other AZ61B tempers and conditions
AZ61B is also supplied in 3 other conditions. The full side-by-side table is on the AZ61B overview.
- FDefaultStandard stocked condition for AZ61B extrusions; best combination of strength, ductility and cost.230 MPa yield · 60 HB
- T5Pick when a modest yield-strength gain over F is needed on heavy extrusions, accepting lower elongation.250 MPa yield · 65 HB
Working with AZ61B-T5
Is AZ61B easy to machine?
Outstanding machinability — high speeds, low cutting forces, sharp positive-rake tools, dry or with mineral oil; never use water-based coolant on fine chips and keep swarf collected (fire risk, no water extinguishers).
Can AZ61B be welded?
Readily GTAW/GMAW welded with AC or pulsed DC using AZ61A/AZ92A filler under argon; preheat 150–250 °C for thick sections, stress relieve to avoid SCC, avoid oxyfuel and flux-heavy processes.
Can AZ61B be formed, bent or molded?
Hot extrudes and forges well at 300–400 °C; cold formability is poor — bend, draw or spin at 200–300 °C with generous radii (min bend radius ≈ 5–7 t cold).
What surface finishes work on AZ61B?
Always apply a chromate-free conversion coat, Dow 17/HAE or plasma-electrolytic anodize followed by epoxy primer/topcoat; isolate from steel, brass and carbon fasteners to prevent galvanic pitting.
AZ61B 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 solid-solution/Mg17Al12 strengthener | 5.8 – 7.2 | 6.5 |
| Zn | 0.4 – 1.5 | 0.9 |
| MnMn controls Fe for corrosion resistance | 0.15 – 0.5 | 0.25 |
| Si | ≤ 0.1 | — |
| Cumax; B-variant limits are slightly more permissive than AZ61A (secondary-metal tolerance) | ≤ 0.05 | — |
| Ni | ≤ 0.01 | — |
| Fe | ≤ 0.01 | — |
| Camax, where specified | ≤ 0.03 | — |
| Others (each)total others 0.30 max | ≤ 0.05 | — |
| Mg | balance | — |
AZ61B-T5 — frequently asked
What is AZ61B-T5 used for?
AZ61B-T5 is typically used for structural extrusions and profiles, aircraft fittings, forged brackets and levers, bicycle and frame tubing, portable equipment housings and welded frame assemblies. In short: higher-strength wrought magnesium.
What is the yield strength of AZ61B-T5?
AZ61B-T5 has a typical yield strength of 250 MPa (36.3 ksi) and a tensile strength of 320 MPa (46.4 ksi) — stronger than 97% of magnesium alloy grades. Strength varies by condition: see the 4 listed tempers.
Is AZ61B-T5 easy to machine?
Yes — machinability is rated excellent (95/100, better than 54% of magnesium alloy grades). Outstanding machinability — high speeds, low cutting forces, sharp positive-rake tools, dry or with mineral oil; never use water-based coolant on fine chips and keep swarf collected (fire risk, no water extinguishers).
Can AZ61B-T5 be welded?
Yes — weldability is rated very good (70/100). Readily GTAW/GMAW welded with AC or pulsed DC using AZ61A/AZ92A filler under argon; preheat 150–250 °C for thick sections, stress relieve to avoid SCC, avoid oxyfuel and flux-heavy processes.
What surface finishes work on AZ61B-T5?
Always apply a chromate-free conversion coat, Dow 17/HAE or plasma-electrolytic anodize followed by epoxy primer/topcoat; isolate from steel, brass and carbon fasteners to prevent galvanic pitting.
Can AZ61B-T5 be formed, bent or molded?
Hot extrudes and forges well at 300–400 °C; cold formability is poor — bend, draw or spin at 200–300 °C with generous radii (min bend radius ≈ 5–7 t cold).
What is the maximum service temperature of AZ61B-T5?
AZ61B-T5 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 AZ61B-F and AZ61B-T5?
F is the default condition — standard stocked condition for AZ61B extrusions; best combination of strength, ductility and cost. T5: pick when a modest yield-strength gain over F is needed on heavy extrusions, accepting lower elongation. Yield strength is 230 MPa in F versus 250 MPa in T5.
Can FabDigit make parts in AZ61B-T5?
Yes — AZ61B-T5 is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM B107/B107M — Magnesium-Alloy Extruded Bars, Rods, Profiles, Tubes, and Wire — ASTM International (2013)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials (Magnesium alloys) — ASM International (1990)
- ASM Handbook Vol.13B — Corrosion: Materials (Magnesium) — ASM International (2005)
- DIN 1729 / material 3.5612 (MgAl6Zn) wrought magnesium alloys — DIN (1982)
- AWS A5.19 — Specification for Magnesium Alloy Welding Electrodes and Rods — AWS (1992)
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.