Introduction
771.0 is an aluminum-zinc alloy grade covered by ASTM B26/B26M. Typical family applications include decorative castings, furniture parts, farm-machinery components, machine-tool parts and large or intricate castings.
| Field | Value |
|---|---|
| Designation | 771.0 |
| Material Type | Aluminum Alloy |
| Sub Type | Aluminum-Zinc 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 | 771.0 | UNS A07710 |
Related Casting Products
Physical Properties
N/A
Chemical Composition
| Element | ASTM B26/B26MEdition 05 · wt.% |
|---|---|
| Si | ≤ 0.15 |
| Fe | ≤ 0.15 |
| Cu | ≤ 0.10 |
| Mn | ≤ 0.10 |
| Mg | 0.8–1.0 |
| Cr | 0.06–0.20 |
| Zn | 6.5–7.5 |
| Ti | 0.10–0.20 |
| Al | remainder |
Notes
ASTM B26/B26M · Edition 05
[1] Chemical composition: Other elements, each: ≤ 0.05 wt.%
[2] Chemical composition: Other elements, total: ≤ 0.15 wt.%
Heat Treatment
ASTM B26/B26M–05 · Sand Casting · T5 · Recommended heat treatment
| Step | Operation | Temperature | Cooling |
|---|---|---|---|
| 1 | Recommended: Precipitation heat treatment | 355 °F / 180 °C; Holding time: 3–5 h[1] | Still air outside furnace |
ASTM B26/B26M–05 · Sand Casting · T51 · Recommended heat treatment
| Step | Operation | Temperature | Cooling |
|---|---|---|---|
| 1 | Recommended: Precipitation heat treatment | 405 °F / 205 °C; Holding time: 6 h[2] | Still air outside furnace |
ASTM B26/B26M–05 · Sand Casting · T52 · Recommended heat treatment
| Step | Operation | Temperature | Cooling |
|---|---|---|---|
| 1 | Recommended: Precipitation heat treatment | 330 °F / 165 °C; Holding time: 6–16 h[3] | 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] T5, T5 · 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] T5, 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
[3] T5, T52, T52 · 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).; Stress relieve for dimensional stability: hold at 775 ± 25°F for 5 h; furnace cool to 650°F for 2 or more h; furnace cool to 450°F for not more than 3/4 h; furnace cool to 250°F for approximately 2 h; cool to room temperature in still air outside the furnace.; Time required depends on variations in cooling rate between 650°F and 450°F during stress-relief procedure (Footnote J).; No quenching required. Cool in still air outside the furnace.; ±5°C; Stress relieve for dimensional stability: hold at 415 ± 15°C for 5 h; furnace cool to 345°C for 2 or more h; furnace cool to 230°C for not more than 3/4 h; furnace cool to 120°C for approximately 2 h; Time required depends on variations in cooling rate between 345°C and 230°C during stress-relief procedure (Footnote J).
[4] 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.; No quenching required. Cool in still air outside the furnace.; ±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] 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
[6] 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.; No quenching required. Cool in still air outside the furnace.; ±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.
[7] 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 2 — Informative
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-zinc alloy ASTM B26/B26M 771.0 has documented applications in impellers, pump heads, suction adapters and volutes. Other cast components used in this material family include decorative castings, furniture parts, farm-machinery components, machine-tool parts and large or intricate castings. Applications include selected machinery, industrial hardware and appearance-oriented products.
Drive hubs, rollers and pump components remain attached to the grades for which they are documented; aluminum-zinc castings are not zinc-base die-casting or wrought aerospace alloys.
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