# 4047 (BAlSi-4) Aluminum

4047 aluminum is a 4000-series aluminum alloy. The main alloying addition is silicon. Cited properties are appropriate for the as-fabricated (no temper or treatment) condition. 4047 is the Aluminum Association (AA) designation for this material. In European standards, it will be given as EN AW-4047. BAlSi-4 is the AWS designation. Additionally, the UNS number is A94047.

It originally received its standard designation in 1964.

The graph bars on the material properties cards below compare 4047 aluminum to: 4000-series alloys (top), all aluminum alloys (middle), and the entire database (bottom). A full bar means this is the highest value in the relevant set. A half-full bar means it's 50% of the highest, and so on.

## Mechanical Properties

Elastic (Young's, Tensile) Modulus

72 *GPa* 10 *x 10 ^{6} psi*

Elongation at Break

3.4 *%*

Fatigue Strength

45 *MPa* 6.6 *x 10 ^{3} psi*

Poisson's Ratio

0.33

Shear Modulus

27 *GPa* 3.9 *x 10 ^{6} psi*

Shear Strength

69 *MPa* 10 *x 10 ^{3} psi*

Tensile Strength: Ultimate (UTS)

120 *MPa* 17 *x 10 ^{3} psi*

Tensile Strength: Yield (Proof)

64 *MPa* 9.2 *x 10 ^{3} psi*

## Thermal Properties

Brazing Temperature

580 to 600 *°C* 1080 to 1120 *°F*

Latent Heat of Fusion

570 *J/g*

Maximum Temperature: Mechanical

160 *°C* 320 *°F*

Melting Completion (Liquidus)

580 *°C* 1080 *°F*

Melting Onset (Solidus)

580 *°C* 1070 *°F*

Specific Heat Capacity

900 *J/kg-K* 0.22 *BTU/lb-°F*

Thermal Conductivity

130 *W/m-K* 77 *BTU/h-ft-°F*

Thermal Expansion

21 *µm/m-K*

## Electrical Properties

Electrical Conductivity: Equal Volume

33 *% IACS*

Electrical Conductivity: Equal Weight (Specific)

120 *% IACS*

## Otherwise Unclassified Properties

Base Metal Price

9.5 *% relative*

Density

2.5 *g/cm ^{3}* 160

*lb/ft*

^{3}Embodied Carbon

7.7 *kg CO _{2}/kg material*

Embodied Energy

140 *MJ/kg* 62 *x 10 ^{3} BTU/lb*

Embodied Water

1050 *L/kg* 130 *gal/lb*

## Common Calculations

Resilience: Ultimate (Unit Rupture Work)

3.5 *MJ/m ^{3}*

Resilience: Unit (Modulus of Resilience)

28 *kJ/m ^{3}*

Stiffness to Weight: Axial

16 *points*

Stiffness to Weight: Bending

55 *points*

Strength to Weight: Axial

13 *points*

Strength to Weight: Bending

21 *points*

Thermal Diffusivity

59 *mm ^{2}/s*

Thermal Shock Resistance

5.6 *points*

## Alloy Composition

Among wrought aluminum alloys, the composition of 4047 aluminum is notable for containing a comparatively high amount of silicon (Si). Silicon is used to increase strength at the expense of ductility. It also lowers the melting temperature and raises the fluidity of the alloy.

Al | 85.3 to 89 | |

Si | 11 to 13 | |

Fe | 0 to 0.8 | |

Cu | 0 to 0.3 | |

Zn | 0 to 0.2 | |

Mn | 0 to 0.15 | |

Mg | 0 to 0.1 | |

res. | 0 to 0.15 |

All values are % weight. Ranges represent what is permitted under applicable standards.

## Followup Questions

## Similar Alloys

## Further Reading

AWS A5.8: Specification for Filler Metals for Brazing and Braze Welding

Aluminum Standards and Data, Aluminum Association Inc., 2013

ASM Specialty Handbook: Aluminum and Aluminum Alloys, J. R. Davis (editor), 1993