304 / 304H

304 / 304H

Dual certified 304/304H is used as a material of construction up to 1500°F. Slight scaling begins at about 1200°F. This is the 0.04% minimum carbon version of type 304 stainless. It has general corrosion resistance similar to the low carbon 304/304L. However, it is subject to carbide precipitation in the heat affected zone (HAZ) of welds. Weldments may be sensitive to HAZ intergranular corrosion in oxidizing acid environments, and to polythionic acid stress corrosion cracking. The carbide precipitation is not harmful to high temperature mechanical properties.

304/304H is welded using the 22Cr 11Ni filler wire (ER308), or covered electrodes (E308). Post-weld heat treatment is not necessary for most high temperature service.

Chemistry

 CrNiCMnSiPSFe
MIN 18.0 8.0 0.04 - - - - -
MAX 20.0 10.5 0.10 2.0 0.75 0.04 0.03 Balance

Specifications

AMS 5513
ASME SA 240
ASTM A 240, ASTM A 959
EN 1.4301
UNS S30400, UNS S30409
W. Nr./EN 1.4948
Werkstoff 1.4301

Inventory

304 / 304H Plate, 304 / 304H Welding Products

Common Trade Names

304H Stainless

Features

  • Elevated temperature service to 1500°F
  • Corrosion resistance similar to 304/304L

Applications

  • Pressure Vessels
  • Petrochemical Equipment

Physical Properties

Density: 0.285 lb/inch3

Temperature, °F 212 1600
Coefficient* of Thermal Expansion, in/in°F x 10-6 9.4 -
Thermal Conductivity
Btu • ft/ft2 • hr • °F
9.4 10.9

* 70°F to indicated temperature.

Mechanical Properties

Representative Tensile Properties

  Minimum Typical
Ultimate Tensile Strength, ksi 75 90
0.2% Yield Strength, ksi 30 35
Elongation, % 40 60

Maximum Allowable Stresses, ASME Section VIII, Div 1 Temperature, °

Temperature, °F 200 400 600 800 1000 1200 1400 1500
stress, ksi 20.0 18.3 16.6 15.2 14.0 6.1 2.3 1.4