355.0 Aluminum-Silicon Alloy Casting Material
Aluminum-Silicon Alloy
Introduction
355.0 is an aluminum-silicon alloy grade covered by ASTM B26/B26M. Typical applications include crankcases, engine blocks, flywheel housings, rear-axle housings and transmission cases.
| Field | Value |
|---|---|
| Designation | 355.0 |
| Material Type | Aluminum Alloy |
| Sub Type | Aluminum-Silicon Alloy |
| Product Form | casting |
Manufacturing Process
Sand Casting
Equivalent Materials
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 | 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
Core Mechanical Properties
Conditions are not identical. Compare each stated condition and applicability separately.
ASTM B26/B26M — 05 · Table 2 — Normative
ASTM B26/B26M — 05 · Table 3 — Normative
Notes
ASTM B26/B26M · Edition 05
[1] Tensile Strength/Yield Strength (Rp0.2)/Elongation: inch-pound; 2 in. or 4 x diameter
[2] Brinell Hardness: inch-pound; 2 in. or 4 x diameter; 500 kgf; 10 mm; Typical hardness is for information only, not required for acceptance
[3] Tensile Strength/Yield Strength (Rp0.2)/Elongation: SI; 5 x diameter
[4] Brinell Hardness: SI; 5 x diameter; 500 kgf; 10 mm; Typical hardness is for information only, not required for acceptance
Welding Conditions
N/A
Applications
Aluminum-silicon alloy ASTM B26/B26M 355.0 is used for crankcases, engine blocks, flywheel housings, rear-axle housings and transmission cases. Other documented applications include electric-motor parts, impellers and water jackets. Other cast components used in this material family include engine-related castings, motor housings and pump parts.
Applications include automotive and industrial machinery, original equipment manufacture, repair and replacement supply. The specified alloy, temper and sand-casting purchase scope remain applicable; general automotive examples do not confer aerospace or safety-critical approval.
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