Aluminum ZL101A-T61
Temper
JIS AC4CH
T61 = t6 variant, underaged
Longer/hotter age than T6 for maximum hardness and machining stability where ductility can be traded away.
Values for the T61 condition
Other ZL101A tempers and conditions
ZL101A is listed in 7 conditions; see the grade overview at ZL101A.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Cooled from hot working, cold worked and naturally aged | Pick when maximum dimensional stability and low residual stress matter more than strength. | 85 | 165 | 6 | 50 HB | 44 % IACS |
As fabricated | Cheapest condition for low-stress, dimensionally stable parts where strength is not critical. | 90 | 175 | 5 | 55 HB | 43 % IACS |
Solution heat treated and naturally aged | Best ductility and impact toughness; used where parts are straightened, riveted or must absorb energy. | 130 | 235 | 10 | 65 HB | 37 % IACS |
Cooled from hot working and artificially aged | Low-distortion, low-cost strengthening (no solution quench) for thin permanent-mould or low-pressure castings. | 180 | 255 | 4 | 72 HB | 41 % IACS |
Solution heat treated and overaged (stabilized) | Choose for dimensional stability at elevated temperature and better toughness, at ~15% lower strength than T6. | 200 | 250 | 8 | 75 HB | 41 % IACS |
T6Default Solution heat treated and artificially aged | The standard stocked condition: peak strength with useful ductility for wheels, knuckles, structural castings. | 220 | 290 | 6 | 85 HB | 39 % IACS |
T61This page T6 variant, underaged | Longer/hotter age than T6 for maximum hardness and machining stability where ductility can be traded away. | 245 | 310 | 4 | 92 HB | 40 % IACS |
What is ZL101A-T61?
ZL101A-T61 is ZL101A in the T61 temper — longer/hotter age than T6 for maximum hardness and machining stability where ductility can be traded away. ZL101A-T61 has a yield strength of 245 MPa (35.5 ksi) and a tensile strength of 310 MPa (45 ksi) — stronger than 64% of aluminum grades. Elongation at break is 4% and the elastic modulus is 72 GPa (10.4 Msi). ZL101A-T61 has a density of 2.68 g/cm³ (0.0968 lb/in³), lighter than 72% of aluminum grades. It melts at 557°C (1,035 °F). T6 is the default condition FabDigit quotes; T61 is available on request or by drawing note.
Limitations
- Limited formability — 8/100, worse than 88% of aluminum grades
ZL101A-T61 properties
Typical room-temperature values for ZL101A-T61; 22 are specific to this condition. Other listed values are ZL101A reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
ZL101A-T61 has a density of 2.68 g/cm³ (0.0968 lb/in³), lighter than 72% of aluminum grades. It melts at 557°C (1,035 °F).
Mechanical13
ZL101A-T61 has a yield strength of 245 MPa (35.5 ksi) and a tensile strength of 310 MPa (45 ksi) — stronger than 64% of aluminum grades. Elongation at break is 4% and the elastic modulus is 72 GPa (10.4 Msi).
Thermal6
ZL101A-T61 is rated for continuous service to 150°C (302 °F). It conducts heat at 153 W/m·K (88.4 BTU/hr·ft·°F), better than 68% of aluminum grades. Thermal expansion is 21.5 µm/m·K (11.9 µin/in·°F).
Electrical3
ZL101A-T61 conducts electricity at 40 % IACS, better than 72% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (60/100), better than 62% of aluminum grades.
Sustainability4
Producing a kilogram of ZL101A-T61 takes about 200 MJ of energy and emits 12.5 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 40%.
Manufacturability7
ZL101A-T61's machinability is good (65/100, better than 62% of aluminum grades); weldability very good (75/100); formability not recommended (8/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with ZL101A-T61
Is ZL101A easy to machine?
Machines freely with sharp PCD or polished-flute carbide tools and high speed; the Si eutectic is abrasive, so coolant and PCD tooling pay off in production.
Can ZL101A be welded?
Readily TIG/MIG welded with ER4043 or ER4047 filler (ER5356 if anodizing colour match is needed); re-solution + re-age after welding to restore T6 properties.
Can ZL101A be formed, bent or molded?
Excellent fluidity and pressure tightness for gravity, low-pressure and sand casting; use Sr modification, Al-5Ti-1B refinement and directional solidification to avoid shrink porosity.
What surface finishes work on ZL101A?
Takes hard and sulphuric anodize for wear/corrosion protection but with a dark grey silicon-mottled look; powder coat, chromate-free conversion coat or paint for decorative parts, and shot-peen to boost fatigue life.
ZL101A 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 |
|---|---|---|
| SiSr or Na modified for fine eutectic | 6.5 – 7.5 | 7 |
| MgMg2Si precipitation hardening | 0.25 – 0.45 | 0.35 |
| Tigrain refiner (Al-Ti-B) | 0.08 – 0.2 | 0.13 |
| Fe≤0.12 typical for premium/A356.2 ingot | ≤ 0.2 | — |
| Cu | ≤ 0.1 | — |
| Mn | ≤ 0.1 | — |
| Zn | ≤ 0.1 | — |
| Others (each)total ≤0.15 | ≤ 0.05 | — |
| Al | balance | — |
ZL101A-T61 — frequently asked
What is ZL101A-T61 used for?
ZL101A-T61 is typically used for automotive wheels, aerospace castings and structural brackets. In short: high-purity A356 equivalent; best ductility of the AlSi7Mg castings; weldable and heat treatable.
What is the yield strength of ZL101A-T61?
ZL101A-T61 has a typical yield strength of 245 MPa (35.5 ksi) and a tensile strength of 310 MPa (45 ksi) — stronger than 64% of aluminum grades. Strength varies by condition: see the 7 listed tempers.
Is ZL101A-T61 easy to machine?
Reasonably — machinability is rated good (65/100, better than 62% of aluminum grades). Machines freely with sharp PCD or polished-flute carbide tools and high speed; the Si eutectic is abrasive, so coolant and PCD tooling pay off in production.
Can ZL101A-T61 be welded?
Yes — weldability is rated very good (75/100). Readily TIG/MIG welded with ER4043 or ER4047 filler (ER5356 if anodizing colour match is needed); re-solution + re-age after welding to restore T6 properties.
What surface finishes work on ZL101A-T61?
Takes hard and sulphuric anodize for wear/corrosion protection but with a dark grey silicon-mottled look; powder coat, chromate-free conversion coat or paint for decorative parts, and shot-peen to boost fatigue life.
Can ZL101A-T61 be formed, bent or molded?
Excellent fluidity and pressure tightness for gravity, low-pressure and sand casting; use Sr modification, Al-5Ti-1B refinement and directional solidification to avoid shrink porosity.
What is the maximum service temperature of ZL101A-T61?
ZL101A-T61 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 ZL101A-T6 and ZL101A-T2?
T6 is the default condition — the standard stocked condition: peak strength with useful ductility for wheels, knuckles, structural castings. T2: pick when maximum dimensional stability and low residual stress matter more than strength. Yield strength is 220 MPa in T6 versus 85 MPa in T2.
Sources
- ASTM B26/B26M and B108/B108M (A356.0 castings) — ASTM (2022)
- ASM Handbook Vol.2 — Properties of Aluminum Casting Alloys — ASM International (1990)
- ASM Handbook Vol.13B — Corrosion of Aluminum Alloys — ASM International (2005)
- JIS H5202 (AC4CH) — JSA (2010)
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.