Introduction
355.0 is a casting grade in the Aluminum-Silicon Alloy family, specified in ASTM B26/B26M. The specification defines its chemical composition and mechanical requirements for the applicable sand-casting tempers. Casting process options include Sand Casting, subject to the applicable specification and component requirements.
| Field | Value |
|---|---|
| Designation | 355.0 |
| Material Type | Aluminum Alloy |
| Sub Type | Aluminum-Silicon Alloy |
| Product Form | casting |
Manufacturing Process
Sand Casting
Equivalent Grades
N/A
Similar Materials
N/A
Reference Standards
| Standard | Standard Title | Edition | Specification | Identifier |
|---|---|---|---|---|
| ASTM B26/B26M | Standard Specification for Aluminum-Alloy Sand Castings | 05 | 355.0 | UNS A03550 |
Related Casting Products
Physical Properties
N/A
Chemical Composition
| Element | ASTM B26/B26MEdition 05 · wt.% |
|---|---|
| Si | 4.5–5.5 |
| Fe | ≤ 0.6[1] |
| Cu | 1.0–1.5 |
| Mn | ≤ 0.50[1] |
| Mg | 0.40–0.6 |
| Cr | ≤ 0.25 |
| Zn | ≤ 0.35 |
| Ti | ≤ 0.25 |
| Al | remainder |
Notes
ASTM B26/B26M · Edition 05
[1] Fe/Mn: If iron exceeds 0.45 %, manganese content shall not be less than one half of the iron content.
[2] Chemical composition: Other elements, each: ≤ 0.05 wt.%
[3] Chemical composition: Other elements, total: ≤ 0.15 wt.%
Heat Treatment
ASTM B26/B26M–05 · Sand Casting · T51 · Recommended heat treatment
| Step | Operation | Temperature / holding time | Cooling |
|---|---|---|---|
| 1 | Recommended: Precipitation heat treatment | 440 °F / 225 °C; Holding time: 7–9 h[1] | Still air outside furnace |
ASTM B26/B26M–05 · Sand Casting · T6 · Recommended heat treatment
ASTM B26/B26M–05 · Sand Casting · T71 · Recommended heat treatment
Notes
ASTM B26/B26M · Edition 05
[1] T51, T51 · Recommended heat treatment: Source: ASTM B917/B917M–25 (Recommended; when specified by the material specification or purchase order).; ±10°F; Use suitable metal-temperature measurement; sections/microstructure affect soak time selection (7.2).; No quenching required. Cool in still air outside the furnace.; ±5°C
[2] T6, T6 · Recommended heat treatment: Source: ASTM B917/B917M–25 (Recommended; when specified by the material specification or purchase order).; ±10°F; Use suitable metal-temperature measurement; sections/microstructure affect soak time selection (7.2).; Quench in water at 150 to 212°F except as noted.; Time at solution temperature may be increased for section thickness over 1 in.; ±5°C; Quench in water at 65 to 100°C except as noted.; Time at solution temperature may be increased for section thickness over 25 mm.
[3] T6, T6 · Recommended heat treatment: Source: ASTM B917/B917M–25 (Recommended; when specified by the material specification or purchase order).; ±10°F; Use suitable metal-temperature measurement; sections/microstructure affect soak time selection (7.2).; No quenching required. Cool in still air outside the furnace.; ±5°C
[4] T71, T71 · Recommended heat treatment: Source: ASTM B917/B917M–25 (Recommended; when specified by the material specification or purchase order).; ±10°F; Use suitable metal-temperature measurement; sections/microstructure affect soak time selection (7.2).; Quench in water at 150 to 212°F except as noted.; Time at solution temperature may be increased for section thickness over 1 in.; ±5°C; Quench in water at 65 to 100°C except as noted.; Time at solution temperature may be increased for section thickness over 25 mm.
[5] T71, T71 · Recommended heat treatment: Source: ASTM B917/B917M–25 (Recommended; when specified by the material specification or purchase order).; ±10°F; Use suitable metal-temperature measurement; sections/microstructure affect soak time selection (7.2).; No quenching required. Cool in still air outside the furnace.; ±5°C
Mechanical Properties
Conditions are not identical. Compare each stated condition and applicability separately.
| Property | ASTM B26/B26MEdition 05T51 | ASTM B26/B26MEdition 05T6 | ASTM B26/B26MEdition 05T71 |
|---|---|---|---|
| Elongation | Not Applicable Not Applicable | ≥ 2.0 %[1] | Not Applicable Not Applicable |
| Tensile Strength | ≥ 25.0 ksi / ≥ 170 MPa[2] | ≥ 32.0 ksi / ≥ 220 MPa[1] | ≥ 30.0 ksi / ≥ 205 MPa[3] |
| Yield Strength (Rp0.2) | ≥ 18.0 ksi / ≥ 125 MPa[2] | ≥ 20.0 ksi / ≥ 140 MPa[1] | ≥ 22.0 ksi / ≥ 150 MPa[3] |
| Brinell Hardness | 65 HB[4] | 80 HB[5] | 75 HB[6] |
Notes
ASTM B26/B26M · Edition 05
[1] Elongation/Tensile Strength/Yield Strength (Rp0.2); T6: inch-pound; 2 in. or 4 x diameter / SI; 5 x diameter
[2] Tensile Strength/Yield Strength (Rp0.2); T51: inch-pound; 2 in. or 4 x diameter / SI; 5 x diameter
[3] Tensile Strength/Yield Strength (Rp0.2); T71: inch-pound; 2 in. or 4 x diameter / SI; 5 x diameter
[4] Brinell Hardness; T51: inch-pound; 2 in. or 4 x diameter; 500 kgf; 10 mm; Typical hardness is for information only, not required for acceptance / SI; 5 x diameter; Typical hardness is for information only, not required for acceptance
[5] Brinell Hardness; T6: inch-pound; 2 in. or 4 x diameter; 500 kgf; 10 mm; Typical hardness is for information only, not required for acceptance / SI; 5 x diameter; Typical hardness is for information only, not required for acceptance
[6] Brinell Hardness; T71: inch-pound; 2 in. or 4 x diameter; 500 kgf; 10 mm; Typical hardness is for information only, not required for acceptance / SI; 5 x diameter; Typical hardness is for information only, not required for acceptance
Welding Conditions
N/A
Applications
At the material-family level, typical applications include custom, shaped aluminum sand-cast components for non-aerospace use. ASTM B26/B26M excludes aerospace applications; suitability of this grade must be checked against the component requirements and specified temper.
Last Updated: October 13, 2026