TP 304H Stainless Steel: Meaning and Specifications

Meaning of TP 304H Stainless Steel

TP 304H stainless steelis a high-carbon austenitic stainless steel specified under ASME SA 240 and ASTM A240, also known as SA 240 GR 304H, AISI 304H, UNS S30409, or EN 1.4948. The "TP" stands for "Type," indicating the specific grade in ASME standards, while "304H" denotes a high-carbon (0.04-0.10%) variant of 304, optimized for enhanced creep and rupture strength in high-temperature applications up to 1500°F (815°C). Non-magnetic in the annealed state, it’s ideal for pressure vessels, boilers, and high-temperature piping. Gangsteel supplies certified TP 304H plates. Contact admin@gangsteel.com or visit our ASME SA240 Stainless sheet.

Chemical Composition of TP 304H Stainless Steel

The composition of TP 304H stainless steel supports high-temperature performance:

Higher carbon enhances creep resistance, while chromium/nickel ensures corrosion resistance. For comparisons, see sa240 gr 304.

Mechanical Properties

The mechanical properties of TP 304H stainless steel for annealed plates (8-75 mm thick) include:

Superior creep strength at 1000°F (25.5 ksi allowable stress). See sa240 gr 304l.

Physical Properties

• Density: 8.00 g/cm³.
• Melting Point: 1400-1450°C.
• Thermal Conductivity: 16.2 W/m·K.
• Coefficient of Thermal Expansion: 17.2 × 10⁻⁶/K.
• Service Temperature: Up to 1500°F (815°C) continuous.

Ideal for high-heat designs. For alternatives, see sa240 gr 316l.

Corrosion Resistance

TP 304H stainless steelresists mild acids and atmospheric conditions but is less effective against chlorides. Higher carbon may reduce weld zone resistance without annealing. See sa240 gr 317l.

Weldability

Fair weldability with ER308H fillers; annealing needed to avoid sensitization. For better welds, see sa240 gr 321.

Applications

TP 304H stainless steelis used in boilers, heat exchangers, power generation, and high-temperature piping. For pricing ($1.60/kg FOB), contact admin@gangsteel.com or visit sa240 gr 304h.