# Half-Hard 302 Stainless Steel

Half-hard AISI 302 is AISI 302 stainless steel in the half-hard temper. The graph bars on the material properties cards below compare half-hard AISI 302 to: wrought austenitic stainless steels (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

350

Elastic (Young's, Tensile) Modulus

200 *GPa* 29 *x 10 ^{6} psi*

Elongation at Break

11 *%*

Fatigue Strength

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

Poisson's Ratio

0.28

Shear Modulus

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

Shear Strength

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

Tensile Strength: Ultimate (UTS)

1170 *MPa* 170 *x 10 ^{3} psi*

Tensile Strength: Yield (Proof)

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

## Thermal Properties

Latent Heat of Fusion

280 *J/g*

Maximum Temperature: Corrosion

410 *°C* 780 *°F*

Maximum Temperature: Mechanical

710 *°C* 1300 *°F*

Melting Completion (Liquidus)

1420 *°C* 2590 *°F*

Melting Onset (Solidus)

1400 *°C* 2550 *°F*

Specific Heat Capacity

480 *J/kg-K* 0.11 *BTU/lb-°F*

Thermal Conductivity

16 *W/m-K* 9.4 *BTU/h-ft-°F*

Thermal Expansion

17 *µm/m-K*

## Electrical Properties

Electrical Conductivity: Equal Volume

2.4 *% IACS*

Electrical Conductivity: Equal Weight (Specific)

2.8 *% IACS*

## Otherwise Unclassified Properties

Base Metal Price

15 *% relative*

Calomel Potential

-70 *mV*

Density

7.8 *g/cm ^{3}* 490

*lb/ft*

^{3}Embodied Carbon

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

Embodied Energy

42 *MJ/kg* 18 *x 10 ^{3} BTU/lb*

Embodied Water

140 *L/kg* 17 *gal/lb*

## Common Calculations

PREN (Pitting Resistance)

19

Resilience: Ultimate (Unit Rupture Work)

120 *MJ/m ^{3}*

Resilience: Unit (Modulus of Resilience)

1870 *kJ/m ^{3}*

Stiffness to Weight: Axial

14 *points*

Stiffness to Weight: Bending

25 *points*

Strength to Weight: Axial

42 *points*

Strength to Weight: Bending

32 *points*

Thermal Diffusivity

4.4 *mm ^{2}/s*

Thermal Shock Resistance

25 *points*

## Alloy Composition

Fe | 67.9 to 75 | |

Cr | 17 to 19 | |

Ni | 8.0 to 10 | |

Mn | 0 to 2.0 | |

Si | 0 to 0.75 | |

C | 0 to 0.15 | |

N | 0 to 0.1 | |

P | 0 to 0.045 | |

S | 0 to 0.030 |

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

## Followup Questions

## Further Reading

ASTM A666: Standard Specification for Annealed or Cold-Worked Austenitic Stainless Steel Sheet, Strip, Plate, and Flat Bar

ASTM A276: Standard Specification for Stainless Steel Bars and Shapes

Welding Metallurgy and Weldability of Stainless Steels, John C. Lippold and Damian J. Kotecki, 2005

ASTM A959: Standard Guide for Specifying Harmonized Standard Grade Compositions for Wrought Stainless Steels

Corrosion of Austenitic Stainless Steels: Mechanism, Mitigation and Monitoring, H. S. Khatak and B. Raj (editors), 2002

Pressure Vessels: External Pressure Technology, 2nd ed., Carl T. F. Ross, 2011

Austenitic Stainless Steels: Microstructure and Mechanical Properties, P. Marshall, 1984

Properties and Selection: Irons, Steels and High Performance Alloys, ASM Handbook vol. 1, ASM International, 1993

ASM Specialty Handbook: Stainless Steels, J. R. Davis (editor), 1994

Advances in Stainless Steels, Baldev Raj et al. (editors), 2010