Aluminum ZL104
GB ZL104 · EN AC-43000 · JIS AC4B
ZL104 (AC4B, EN AC-43000) is a GB/T 1173 AlSi9Mg sand and permanent-mold casting alloy available as-cast (F) and in T1, T5 and T6, broadly comparable to 359.0.
Reference datasheet — ZL104 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the T6 condition
ZL104 tempers and conditions
ZL104 is supplied in 4 conditions, soft to hard. T6 is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As fabricated | Cheapest condition for lightly loaded, dimensionally stable housings where heat-treatment distortion is unwanted. | 85 | 175 | 3.5 | 55 HB | 36 % IACS |
Cooled from hot working and artificially aged | Shop practice for dimensional stabilisation of machined permanent-mold parts; modest strength gain over F. | 130 | 200 | 2.5 | 65 HB | 35 % IACS |
Cooled from hot working and naturally aged | Used for permanent-mold parts needing a strength/stability lift without solution-treatment distortion cost. | 150 | 220 | 2 | 68 HB | 35 % IACS |
T6Default Solution heat treated and artificially aged | Standard structural condition: highest strength and hardness for load-bearing castings such as brackets, pump and gearbox housings. | 200 | 260 | 3 | 75 HB | 33 % IACS |
What is ZL104?
ZL104 (AC4B, EN AC-43000) is a GB/T 1173 AlSi9Mg sand and permanent-mold casting alloy available as-cast (F) and in T1, T5 and T6, broadly comparable to 359.0. The high silicon content gives the fluidity needed for thin-wall housings, brackets and wheel castings, with 200 MPa yield, 260 MPa tensile, 3% elongation, HB 75 and 145 W/m·K thermal conductivity (33% IACS). Elongation and hardness sit below the AlSi7Mg grades, service is capped near 150 °C, and anodizing is protective rather than decorative. Choose ZL101A or A356.0 when ductility and fatigue life matter more than mold fill. ZL104 has a density of 2.65 g/cm³ (0.0957 lb/in³), lighter than 90% of aluminum grades. It melts at 557°C (1,035 °F). ZL104 has a yield strength of 200 MPa (29 ksi) and a tensile strength of 260 MPa (37.7 ksi) — stronger than 53% of aluminum grades. Elongation at break is 3% and the elastic modulus is 71 GPa (10.3 Msi).
What is ZL104 used for?
- housings
- brackets
- wheel castings
Limitations
- Limited formability — 10/100, worse than 80% of aluminum grades
- Limited ductility — 3%, worse than 79% of aluminum grades
- Hard to polish — 45/100, worse than 76% of aluminum grades
ZL104 properties
Typical room-temperature values for ZL104-T6; bars are the position among aluminum grades.
Physical3
ZL104 has a density of 2.65 g/cm³ (0.0957 lb/in³), lighter than 90% of aluminum grades. It melts at 557°C (1,035 °F).
Mechanical12
ZL104 has a yield strength of 200 MPa (29 ksi) and a tensile strength of 260 MPa (37.7 ksi) — stronger than 53% of aluminum grades. Elongation at break is 3% and the elastic modulus is 71 GPa (10.3 Msi).
Thermal6
ZL104 is rated for continuous service to 150°C (302 °F). It conducts heat at 145 W/m·K (83.8 BTU/hr·ft·°F), better than 53% of aluminum grades. Thermal expansion is 21.5 µm/m·K (11.9 µin/in·°F).
Electrical3
ZL104 conducts electricity at 33 % IACS, worse than 57% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (58/100), better than 57% of aluminum grades.
Sustainability4
Producing a kilogram of ZL104 takes about 200 MJ of energy and emits 12.5 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 70%.
Manufacturability8
ZL104's machinability is good (55/100, worse than 59% of aluminum grades); weldability very good (70/100); formability not recommended (10/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the aluminum family
Yield strength against density for every aluminum grade FabDigit runs. ZL104 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with ZL104
Is ZL104 easy to machine?
Machines cleanly with PCD or polished-flute carbide at high speed and generous coolant; the eutectic Si is abrasive, so uncoated HSS wears fast and built-up edge appears at low speeds.
Can ZL104 be welded?
Readily TIG/MIG welded or repair-welded with ER4043/ZL104 filler; re-solution + age after welding to restore T6 properties, and avoid 5000-series-type Mg fillers.
Can ZL104 be formed, bent or molded?
Excellent fluidity for thin-wall sand, permanent-mold and low-pressure castings; requires Sr or Na modification plus directional solidification/risering to avoid coarse eutectic and shrinkage porosity.
ZL104 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 |
|---|---|---|
| SiGB/T 1173 ZAlSi9Mg | 8 – 10.5 | 9 |
| Mgprecipitation strengthening (Mg2Si) | 0.17 – 0.35 | 0.28 |
| Mnneutralises Fe needles | 0.2 – 0.5 | 0.35 |
| Fe≤0.9 % permitted for die/permanent-mold practice in some works standards | ≤ 0.6 | |
| Cuimpurity limit | ≤ 0.1 | |
| Znimpurity limit | ≤ 0.25 | |
| Tigrain refiner residual | ≤ 0.15 | |
| Others (each) | ≤ 0.05 | |
| Others (total) | ≤ 0.15 | |
| Al | balance |
What surface finishes work on ZL104?
Chromate/ chrome-free conversion coating or powder paint works well; sulfuric or hard anodizing gives only a dark grey non-decorative film because of the high Si, and porosity can cause bleed-out.
Surface treatments FabDigit runs on aluminum parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Equivalent designations
Standards and trade names that resolve to Aluminum ZL104 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
How much does ZL104 cost?
ZL104 is a standard-cost aluminum ($$), cheaper than about 71% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
ZL104 — frequently asked
What is ZL104 used for?
ZL104 is typically used for housings, brackets and wheel castings. In short: high-fluidity thin-wall casting; lower cost than AlSi7Mg; protective anodize only.
What is the yield strength of ZL104?
ZL104 has a typical yield strength of 200 MPa (29 ksi) and a tensile strength of 260 MPa (37.7 ksi) — stronger than 53% of aluminum grades. Strength varies by condition: see the 4 listed tempers.
Is ZL104 easy to machine?
Reasonably — machinability is rated good (55/100, worse than 59% of aluminum grades). Machines cleanly with PCD or polished-flute carbide at high speed and generous coolant; the eutectic Si is abrasive, so uncoated HSS wears fast and built-up edge appears at low speeds.
Can ZL104 be welded?
Yes — weldability is rated very good (70/100). Readily TIG/MIG welded or repair-welded with ER4043/ZL104 filler; re-solution + age after welding to restore T6 properties, and avoid 5000-series-type Mg fillers.
What surface finishes work on ZL104?
Chromate/ chrome-free conversion coating or powder paint works well; sulfuric or hard anodizing gives only a dark grey non-decorative film because of the high Si, and porosity can cause bleed-out.
Can ZL104 be formed, bent or molded?
Excellent fluidity for thin-wall sand, permanent-mold and low-pressure castings; requires Sr or Na modification plus directional solidification/risering to avoid coarse eutectic and shrinkage porosity.
What is the maximum service temperature of ZL104?
ZL104 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 ZL104-T6 and ZL104-F?
T6 is the default condition — standard structural condition: highest strength and hardness for load-bearing castings such as brackets, pump and gearbox housings. F: cheapest condition for lightly loaded, dimensionally stable housings where heat-treatment distortion is unwanted. Yield strength is 200 MPa in T6 versus 85 MPa in F.
How much does ZL104 cost?
ZL104 is a standard-cost aluminum ($$), cheaper than about 71% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys (359.0 / A356-class data) — ASM International (1990)
- EN 1706 — Aluminium castings, EN AC-43000 (AlSi10Mg) — CEN (2020)
- JIS H5202 — Aluminium alloy castings (AC4B) — JSA (2010)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.