# Type 1 (Unalloyed Reactor Grade, R04200) Niobium

Type 1 niobium is a niobium alloy. Cited properties are appropriate for the annealed condition. R04200 is the UNS number for this material. Additionally, the ASTM designation is Niobium Type 1. It has a moderately low density and a moderately low tensile strength among alloys in the same category.

The graph bars on the material properties cards below compare Type 1 niobium to: niobium alloys (top), all alloys in the same category (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

Brinell Hardness

79

Elastic (Young's, Tensile) Modulus

110 *GPa* 15 *x 10 ^{6} psi*

Elongation at Break

29 *%*

Poisson's Ratio

0.4

Shear Modulus

38 *GPa* 5.4 *x 10 ^{6} psi*

Tensile Strength: Ultimate (UTS)

140 *MPa* 21 *x 10 ^{3} psi*

Tensile Strength: Yield (Proof)

82 *MPa* 12 *x 10 ^{3} psi*

## Thermal Properties

Latent Heat of Fusion

320 *J/g*

Specific Heat Capacity

270 *J/kg-K* 0.065 *BTU/lb-°F*

Thermal Conductivity

52 *W/m-K* 30 *BTU/h-ft-°F*

Thermal Expansion

7.3 *µm/m-K*

## Otherwise Unclassified Properties

Density

8.6 *g/cm ^{3}* 540

*lb/ft*

^{3}Embodied Water

160 *L/kg* 19 *gal/lb*

## Common Calculations

Resilience: Ultimate (Unit Rupture Work)

35 *MJ/m ^{3}*

Resilience: Unit (Modulus of Resilience)

32 *kJ/m ^{3}*

Stiffness to Weight: Axial

6.8 *points*

Stiffness to Weight: Bending

18 *points*

Strength to Weight: Axial

4.6 *points*

Strength to Weight: Bending

7.1 *points*

Thermal Diffusivity

23 *mm ^{2}/s*

Thermal Shock Resistance

13 *points*

## Alloy Composition

Nb | 99.7 to 100 | |

Ta | 0 to 0.1 | |

W | 0 to 0.030 | |

Ti | 0 to 0.020 | |

Zr | 0 to 0.020 | |

Hf | 0 to 0.020 | |

O | 0 to 0.015 | |

C | 0 to 0.010 | |

Mo | 0 to 0.010 | |

N | 0 to 0.010 | |

Si | 0 to 0.0050 | |

Ni | 0 to 0.0050 | |

Fe | 0 to 0.0050 | |

H | 0 to 0.0015 |

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

## Followup Questions

## Similar Alloys

## Further Reading

ASTM B392: Standard Specification for Niobium and Niobium Alloy Bar, Rod, and Wire

ASTM B393: Standard Specification for Niobium and Niobium Alloy Strip, Sheet, and Plate

ASTM B394: Standard Specification for Niobium and Niobium Alloy Seamless and Welded Tubes

Extractive Metallurgy of Niobium, C. K. Gupta and A. K. Suri, 1993