# Annealed R30605 Alloy

Annealed R30605 cobalt is R30605 cobalt in the annealed condition. The graph bars on the material properties cards below compare annealed R30605 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

Elastic (Young's, Tensile) Modulus

210 *GPa* 30 *x 10 ^{6} psi*

Elongation at Break

34 *%*

Fatigue Strength

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

Poisson's Ratio

0.29

Shear Modulus

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

Tensile Strength: Ultimate (UTS)

1130 *MPa* 160 *x 10 ^{3} psi*

Tensile Strength: Yield (Proof)

470 *MPa* 68 *x 10 ^{3} psi*

## Thermal Properties

Latent Heat of Fusion

290 *J/g*

Melting Completion (Liquidus)

1410 *°C* 2570 *°F*

Melting Onset (Solidus)

1330 *°C* 2430 *°F*

Specific Heat Capacity

410 *J/kg-K* 0.1 *BTU/lb-°F*

Thermal Conductivity

9.6 *W/m-K* 5.6 *BTU/h-ft-°F*

Thermal Expansion

12 *µm/m-K*

## Electrical Properties

Electrical Conductivity: Equal Volume

2.0 *% IACS*

Electrical Conductivity: Equal Weight (Specific)

1.8 *% IACS*

## Otherwise Unclassified Properties

Density

9.6 *g/cm ^{3}* 600

*lb/ft*

^{3}Embodied Carbon

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

Embodied Energy

140 *MJ/kg* 60 *x 10 ^{3} BTU/lb*

Embodied Water

450 *L/kg* 53 *gal/lb*

## Common Calculations

Resilience: Ultimate (Unit Rupture Work)

310 *MJ/m ^{3}*

Resilience: Unit (Modulus of Resilience)

520 *kJ/m ^{3}*

Stiffness to Weight: Axial

12 *points*

Stiffness to Weight: Bending

21 *points*

Strength to Weight: Axial

33 *points*

Strength to Weight: Bending

25 *points*

Thermal Diffusivity

2.5 *mm ^{2}/s*

Thermal Shock Resistance

31 *points*

## Alloy Composition

Co | 46.4 to 57 | |

Cr | 19 to 21 | |

W | 14 to 16 | |

Ni | 9.0 to 11 | |

Mn | 1.0 to 2.0 | |

Fe | 0 to 3.0 | |

Si | 0 to 0.4 | |

C | 0.050 to 0.15 | |

P | 0 to 0.040 | |

S | 0 to 0.030 |

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

## Followup Questions

## Further Reading

ASTM F90: Standard Specification for Wrought Cobalt-20Chromium-15Tungsten-10Nickel Alloy for Surgical Implant Applications (UNS R30605)

ASTM F1091: Standard Specification for Wrought Cobalt-20Chromium-15Tungsten-10Nickel Alloy Surgical Fixation Wire (UNS R30605)

ISO 5832-5: Implants for Surgery - Metallic Materials - Part 5: Wrought Cobalt-Chromium-Tungsten-Nickel Alloy

ASM Specialty Handbook: Nickel, Cobalt, and Their Alloys, Joseph R. Davis (editor), 2000