# ASTM A369 Grade FP92 High-Chromium Steel

ASTM A369 grade FP92 is an alloy steel formulated for primary forming into wrought products. Cited properties are appropriate for the normalized and tempered condition.

It has a fairly low thermal conductivity among wrought alloy steels in the same category. In addition, it has a very high base cost and a very high electrical conductivity.

The graph bars on the material properties cards below compare ASTM A369 grade FP92 to: wrought alloy steels in the same category (top), all iron 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

Brinell Hardness

210

Elastic (Young's, Tensile) Modulus

190 *GPa* 28 *x 10 ^{6} psi*

Elongation at Break

19 *%*

Fatigue Strength

330 *MPa* 49 *x 10 ^{3} psi*

Poisson's Ratio

0.28

Shear Modulus

76 *GPa* 11 *x 10 ^{6} psi*

Shear Strength

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

Tensile Strength: Ultimate (UTS)

710 *MPa* 100 *x 10 ^{3} psi*

Tensile Strength: Yield (Proof)

490 *MPa* 71 *x 10 ^{3} psi*

## Thermal Properties

Latent Heat of Fusion

260 *J/g*

Maximum Temperature: Mechanical

590 *°C* 1100 *°F*

Melting Completion (Liquidus)

1490 *°C* 2710 *°F*

Melting Onset (Solidus)

1450 *°C* 2640 *°F*

Specific Heat Capacity

470 *J/kg-K* 0.11 *BTU/lb-°F*

Thermal Conductivity

26 *W/m-K* 15 *BTU/h-ft-°F*

Thermal Expansion

13 *µm/m-K*

## Electrical Properties

Electrical Conductivity: Equal Volume

9.3 *% IACS*

Electrical Conductivity: Equal Weight (Specific)

10 *% IACS*

## Otherwise Unclassified Properties

Base Metal Price

11 *% relative*

Density

7.9 *g/cm ^{3}* 500

*lb/ft*

^{3}Embodied Carbon

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

Embodied Energy

40 *MJ/kg* 17 *x 10 ^{3} BTU/lb*

Embodied Water

89 *L/kg* 11 *gal/lb*

## Common Calculations

PREN (Pitting Resistance)

14

Resilience: Ultimate (Unit Rupture Work)

120 *MJ/m ^{3}*

Resilience: Unit (Modulus of Resilience)

620 *kJ/m ^{3}*

Stiffness to Weight: Axial

14 *points*

Stiffness to Weight: Bending

24 *points*

Strength to Weight: Axial

25 *points*

Strength to Weight: Bending

22 *points*

Thermal Diffusivity

6.9 *mm ^{2}/s*

Thermal Shock Resistance

19 *points*

## Alloy Composition

Among alloy steels, the composition of ASTM A369 grade FP92 is notable for including tungsten (W) and zirconium (Zr). Tungsten interacts with other alloying elements to a greater extent than usual, which makes it hard to broadly characterize its effects. Zirconium is used to improve ductility.

Fe | 85.8 to 89.1 | |

Cr | 8.5 to 9.5 | |

W | 1.5 to 2.0 | |

Mo | 0.3 to 0.6 | |

Mn | 0.3 to 0.6 | |

Si | 0 to 0.5 | |

V | 0.15 to 0.25 | |

Ni | 0 to 0.4 | |

C | 0.070 to 0.13 | |

Nb | 0.040 to 0.090 | |

N | 0.030 to 0.070 | |

P | 0 to 0.020 | |

Al | 0 to 0.020 | |

S | 0 to 0.010 | |

Ti | 0 to 0.010 | |

Zr | 0 to 0.010 | |

B | 0.0010 to 0.0060 |

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

## Followup Questions

## Similar Alloys

## Further Reading

ASTM A369: Standard Specification for Carbon and Ferritic Alloy Steel Forged and Bored Pipe for High-Temperature Service