Aluminum AC4CH
JIS AC4CH · ASTM A356.0
AC4CH is the high-purity, low-iron version of AC4C (A356.2 / AlSi7Mg0.3), where restricted Fe content reduces brittle intermetallics and raises ductility and fatigue strength.
Reference datasheet — AC4CH 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
AC4CH tempers and conditions
AC4CH is supplied in 7 conditions, soft to hard. T6 is the default FabDigit quotes; the values on this page are for it.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As fabricated | Lowest-cost condition for lightly loaded or non-structural castings where dimensional stability after machining is not critical. | 90 | 170 | 5 | 55 HB | 42 % IACS |
Solution heat treated and naturally aged | Choose when maximum ductility and impact energy are wanted with moderate strength, e.g. crash-relevant nodes that are later riveted or straightened. | 120 | 230 | 12 | 60 HB | 38 % IACS |
Solution heat treated and strongly overaged | Use where long-term dimensional stability and machining-stress freedom dominate over strength, e.g. optical/instrument housings. | 140 | 205 | 4 | 60 HB | 41 % IACS |
Cooled from hot working and artificially aged | Use when a strength/stability gain is needed without the distortion risk and cost of solution quenching. | 145 | 200 | 4 | 65 HB | 41 % IACS |
Solution heat treated and overaged (stabilized) | Select for dimensional/thermal stability and lower residual stress in precision or elevated-temperature parts, at some loss of strength. | 205 | 240 | 5 | 75 HB | 40 % IACS |
T6Default Solution heat treated and artificially aged | Default condition for structural and safety-critical castings needing the best combination of strength, elongation and fatigue life. | 210 | 280 | 8 | 85 HB | 39 % IACS |
T6 variant, underaged | Pick for the highest strength/hardness available from AC4CH (JIS min 260 MPa) where some ductility can be traded away. | 240 | 300 | 5 | 95 HB | 39 % IACS |
What is AC4CH?
AC4CH is the high-purity, low-iron version of AC4C (A356.2 / AlSi7Mg0.3), where restricted Fe content reduces brittle intermetallics and raises ductility and fatigue strength. It is used for high-integrity structural and safety-critical castings, reaching 210 MPa yield, 280 MPa tensile, 8 % elongation and 85 HB with 151 W/m·K conductivity in the default condition, and is supplied in tempers from F through T71. Maximum service temperature is about 150 °C, machinability is 60, and the tighter chemistry costs more than AC4C, which remains the alternative for non-critical housings. AC4CH 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). AC4CH has a yield strength of 210 MPa (30.5 ksi) and a tensile strength of 280 MPa (40.6 ksi) — stronger than 56% of aluminum grades. Elongation at break is 8% and the elastic modulus is 72.4 GPa (10.5 Msi).
What is AC4CH used for?
- automotive suspension components
- aerospace castings
- high-strength wheels
AC4CH properties
Typical room-temperature values for AC4CH-T6; bars are the position among aluminum grades.
Physical3
AC4CH 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
AC4CH has a yield strength of 210 MPa (30.5 ksi) and a tensile strength of 280 MPa (40.6 ksi) — stronger than 56% of aluminum grades. Elongation at break is 8% and the elastic modulus is 72.4 GPa (10.5 Msi).
Thermal6
AC4CH is rated for continuous service to 150°C (302 °F). It conducts heat at 151 W/m·K (87.2 BTU/hr·ft·°F), better than 63% of aluminum grades. Thermal expansion is 21.5 µm/m·K (11.9 µin/in·°F).
Electrical3
AC4CH conducts electricity at 39 % IACS, better than 65% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (55/100), worse than 51% of aluminum grades.
Sustainability4
Producing a kilogram of AC4CH takes about 200 MJ of energy and emits 12.5 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 20%.
Manufacturability8
AC4CH's machinability is good (60/100, worse than 51% of aluminum grades); weldability very good (75/100); formability poor (15/100).
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. AC4CH is highlighted; hover a dot for its name, or open the interactive family chart.
Working with AC4CH
Is AC4CH easy to machine?
Machines cleanly with PCD or polished-flute carbide tooling, high speed and low feed; eutectic Si abrades HSS quickly and T6 gives better chip control than as-cast F.
Can AC4CH be welded?
Readily TIG/MIG welded with ER4043/ER4145 filler; re-solution + age locally welded structural castings and avoid weld porosity by degassing/pre-machining oxide skin.
Can AC4CH be formed, bent or molded?
Excellent fluidity and low hot-tearing tendency for sand, permanent-mold, low-pressure and squeeze casting; Sr modification plus Ti-B refinement and directional solidification are needed to keep porosity low for T6 properties.
AC4CH 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 strengthening | 0.25 – 0.45 | 0.35 |
| Felow-Fe is the key difference vs AC4C; A356.2 ingot ≤0.12 | ≤ 0.2 | 0.12 |
| Cu | ≤ 0.2 | 0.05 |
| Mn | ≤ 0.1 | 0.03 |
| Zn | ≤ 0.1 | 0.03 |
| Tigrain refinement with Al-Ti-B | ≤ 0.2 | 0.12 |
| Ni | ≤ 0.05 | |
| Cr | ≤ 0.05 | |
| Al | balance |
What surface finishes work on AC4CH?
Chromate-free conversion coating or powder paint for cosmetics; hard anodize for wear surfaces (grey tone from Si), and shot peening markedly raises fatigue life of T6 castings.
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 AC4CH in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- A356.0
- Similar grades
- A356.2AlSi7Mg0.3
How much does AC4CH cost?
AC4CH 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.
AC4CH — frequently asked
What is AC4CH used for?
AC4CH is typically used for automotive suspension components, aerospace castings and high-strength wheels. In short: low-Fe high-integrity A356; highest elongation in family; safety-critical structural castings.
What is the yield strength of AC4CH?
AC4CH has a typical yield strength of 210 MPa (30.5 ksi) and a tensile strength of 280 MPa (40.6 ksi) — stronger than 56% of aluminum grades. Strength varies by condition: see the 7 listed tempers.
Is AC4CH easy to machine?
Reasonably — machinability is rated good (60/100, worse than 51% of aluminum grades). Machines cleanly with PCD or polished-flute carbide tooling, high speed and low feed; eutectic Si abrades HSS quickly and T6 gives better chip control than as-cast F.
Can AC4CH be welded?
Yes — weldability is rated very good (75/100). Readily TIG/MIG welded with ER4043/ER4145 filler; re-solution + age locally welded structural castings and avoid weld porosity by degassing/pre-machining oxide skin.
What surface finishes work on AC4CH?
Chromate-free conversion coating or powder paint for cosmetics; hard anodize for wear surfaces (grey tone from Si), and shot peening markedly raises fatigue life of T6 castings.
Can AC4CH be formed, bent or molded?
Excellent fluidity and low hot-tearing tendency for sand, permanent-mold, low-pressure and squeeze casting; Sr modification plus Ti-B refinement and directional solidification are needed to keep porosity low for T6 properties.
What is the maximum service temperature of AC4CH?
AC4CH 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 AC4CH-T6 and AC4CH-F?
T6 is the default condition — default condition for structural and safety-critical castings needing the best combination of strength, elongation and fatigue life. F: lowest-cost condition for lightly loaded or non-structural castings where dimensional stability after machining is not critical. Yield strength is 210 MPa in T6 versus 90 MPa in F.
How much does AC4CH cost?
AC4CH 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
- JIS H 5202 Aluminium alloy castings — JSA (2010)
- ASTM B26/B26M & B108 (A356.0) / Aluminum Association Pink Sheets (A356.2 ingot) — ASTM / The Aluminum Association (2018)
- ASM Handbook Vol.2 — Properties of Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol.15 — Casting — ASM International (2008)
- GB/T 1173 ZL101A comparable cast alloy data — SAC (2013)
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.