304H vs 316H Stainless Steel Corrosion and Strength Differen

304H vs 316H Stainless Steel: Corrosion and Strength Differences

At Gangsteel, a leading manufacturer and exporter of stainless steel products, we supply premium SA 240 GR 304H and SA 240 GR 316H stainless steel plates compliant with ASME SA 240 and ASTM A240 standards. 304H stainless steel (UNS S30409, AISI 304H, EN 1.4948) is a high-carbon austenitic grade optimized for high-temperature strength, while 316H stainless steel (UNS S31609, AISI 316H, EN 1.4919) is a high-carbon, molybdenum-enhanced austenitic grade for superior corrosion resistance and high-temperature performance.

 Both are non-magnetic in the annealed state with a density of 8.00 g/cm³. This guide compares 304H vs 316H stainless steel in corrosion resistance, strength, and other properties for applications like boilers, heat exchangers, and SA 240 GR 304 pipe. For inquiries, contact us at admin@gangsteel.com or explore our ASME SA240 Stainless sheet offerings.

Overview of 304H vs 316H Stainless Steel

304H stainless steelis a high-carbon variant of 304, designed for creep resistance in high-temperature environments like power generation. It offers good corrosion resistance in mild conditions.

316H stainless steelis a high-carbon variant of 316, with added molybdenum (2-3%) for enhanced pitting resistance in chlorides, making it suitable for marine and chemical applications at high temperatures.

Both grades are austenitic, with similar formability, but 316H excels in corrosive environments. See our sa240 gr 304h and sa240 gr 316h pages for stock.

Chemical Composition Comparison

The composition differs mainly in molybdenum and carbon, impacting corrosion and strength:

• Molybdenum: Absent in 304H, making 316H superior for pitting in chlorides.
• Carbon: High in both (0.04-0.10%) for creep resistance, but increases sensitization risk during welding.
• Chromium/Nickel: 304H has higher Cr for oxidation, while 316H’s higher Ni improves toughness and corrosion resistance.

For low-carbon variants, see sa240 gr 304l and sa240 gr 316l.

Corrosion Resistance Comparison

Both grades resist corrosion in mild acids and atmospheric conditions, outperforming SS204 vs SS 304.

• 304H: Excellent in non-chloride high-temperature environments (e.g., boilers). Higher carbon risks sensitization in welds, reducing corrosion resistance unless annealed.
• 316H: Superior pitting and crevice corrosion resistance in chloride environments (e.g., marine, chemical) due to 2-3% molybdenum. Better for harsh, corrosive high-temperature settings.

304His ideal for oxidation resistance, while 316H excels in chloride pitting. For enhanced resistance, see sa240 gr 317l.

Strength Comparison

Mechanical properties for annealed plates (8-75 mm thick):

• Tensile Strength: Both 515 MPa, but 316H maintains better strength in corrosive high-heat (e.g., allowable stress 25.5 ksi at 1000°F for both, but 316H resists chlorides).
• Yield Strength: Equal 205 MPa, supporting load-bearing in high-temperature applications.
• High-Temperature Strength: Both offer creep resistance, but 316H’s molybdenum enhances performance in aggressive environments.
• Cold-Working: Both can increase strength (up to 900 MPa tensile) with reduced ductility.

For comparison with other grades, see sa240 gr 304l.

Weldability Comparison

• 304H: Fair with ER308H fillers; higher carbon (0.04-0.10%) risks sensitization, requiring annealing.
• 316H: Fair with ER316H fillers; similar carbon risks, but molybdenum may require additional care to avoid cracking.

Both need controlled welding; low-carbon variants like 304L/316L are better. See sa240 gr 321.

Physical Properties Comparison

Both share identical physical properties due to similar compositions:

• Density: 8.00 g/cm³, ideal for lightweight designs (e.g., a 1m x 1m x 3mm plate weighs ~24 kg).
• Melting Point: 1400-1450°C, suitable for processing.
• Thermal Conductivity: 16.2 W/m·K at 100°C.
• Coefficient of Thermal Expansion: 17.2 × 10⁻⁶/K (20-100°C) for 304H; 16.5 × 10⁻⁶/K for 316H (slightly lower due to Mo).
• Electrical Resistivity: 0.72 × 10⁻⁶ Ω·m for 304H; 0.74 ×10⁻⁶ Ω·m for 316H.

316H’s molybdenum slightly reduces thermal expansion, beneficial for high-temperature stability.

Applications of 304H vs 316H Stainless Steel

• 304H: Boilers, heat exchangers, power generation in non-chloride high-heat environments.
• 316H: Chemical processing, marine equipment, pharmaceuticals in corrosive high-temperature settings.

For cost-effective options, see sa240 gr 201.

Cost Comparison

As of October 19, 2025:

Gangsteel offers competitive rates ($1.60/kg for 304H, $2.50/kg for 316H FOB, MOQ 1 ton). Contact admin@gangsteel.com or visit sa240 gr 304h.

Which is Better for High-Temperature Applications?

• 304H: Better for non-chloride high-heat (e.g., boilers) with lower cost.
• 316H: Superior for corrosive high-temperature environments (e.g., chemical processing) with enhanced pitting resistance.

Summary

304H stainless steelexcels in high-temperature strength (515 MPa tensile) for non-corrosive environments, while 316H stainless steel offers similar strength with superior corrosion resistance in chlorides due to molybdenum. Choose 304H for cost-effective high-heat applications and 316H for harsh, corrosive conditions. Gangsteel offers both at competitive prices. Contact admin@gangsteel.com for quotes.