# UNS R30006 Co-Cr-W Alloy

R30006 cobalt is a cobalt alloy. Cited properties are appropriate for the annealed condition. It has a fairly low ductility among cobalt alloys. In addition, it has a moderately high thermal conductivity and a moderately low tensile strength.

The graph bars on the material properties cards below compare R30006 cobalt to other cobalt alloys (top) 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

Compressive (Crushing) Strength

1520 *MPa* 220 *x 10 ^{3} psi*

Elastic (Young's, Tensile) Modulus

220 *GPa* 32 *x 10 ^{6} psi*

Elongation at Break

1.0 *%*

Fatigue Strength

260 *MPa* 38 *x 10 ^{3} psi*

Poisson's Ratio

0.28

Rockwell C Hardness

40

Shear Modulus

85 *GPa* 12 *x 10 ^{6} psi*

Tensile Strength: Ultimate (UTS)

900 *MPa* 130 *x 10 ^{3} psi*

Tensile Strength: Yield (Proof)

540 *MPa* 78 *x 10 ^{3} psi*

## Thermal Properties

Latent Heat of Fusion

320 *J/g*

Melting Completion (Liquidus)

1400 *°C* 2550 *°F*

Melting Onset (Solidus)

1290 *°C* 2350 *°F*

Specific Heat Capacity

450 *J/kg-K* 0.11 *BTU/lb-°F*

Thermal Conductivity

15 *W/m-K* 8.6 *BTU/h-ft-°F*

Thermal Expansion

11 *µm/m-K*

## Electrical Properties

Electrical Conductivity: Equal Volume

1.6 *% IACS*

Electrical Conductivity: Equal Weight (Specific)

1.7 *% IACS*

## Otherwise Unclassified Properties

Calomel Potential

-250 *mV*

Density

8.6 *g/cm ^{3}* 540

*lb/ft*

^{3}Embodied Carbon

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

Embodied Energy

110 *MJ/kg* 46 *x 10 ^{3} BTU/lb*

Embodied Water

500 *L/kg* 60 *gal/lb*

## Common Calculations

Resilience: Ultimate (Unit Rupture Work)

7.8 *MJ/m ^{3}*

Resilience: Unit (Modulus of Resilience)

670 *kJ/m ^{3}*

Stiffness to Weight: Axial

14 *points*

Stiffness to Weight: Bending

23 *points*

Strength to Weight: Axial

29 *points*

Strength to Weight: Bending

24 *points*

Thermal Diffusivity

3.9 *mm ^{2}/s*

Thermal Shock Resistance

26 *points*

## Alloy Composition

Co | 48.6 to 68.1 | |

Cr | 27 to 32 | |

W | 4.0 to 6.0 | |

Ni | 0 to 3.0 | |

Fe | 0 to 3.0 | |

C | 0.9 to 1.4 | |

Si | 0 to 2.0 | |

Mo | 0 to 1.0 |

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

## Followup Questions

## Similar Alloys

## Further Reading

Properties and Selection: Nonferrous Alloys and Special-Purpose Materials, ASM Handbook vol. 2, ASM International, 1993