Comparison of 316H and 316Ti Stainless Steel: High-Carbon Strengthened vs Titanium-Stabilized Grade

316H and 316Ti are modified grades of 316, with different performance orientations: 316H improves high-temperature creep strength through high carbon content, while 316Ti enhances intergranular corrosion resistance through titanium stabilization. Both are suitable for high-temperature environments, but have clear differences in corrosion resistance and strength requirements.

Core Parameter Comparison

Parameter	316H Stainless Steel	316Ti Stainless Steel
Chemical Composition (wt%)	C=0.04-0.10, Cr=16.00-18.00, Ni=10.00-14.00, Mo=2.00-3.00, Fe=Balance	C≤0.08, Cr=16.00-18.00, Ni=10.00-14.00, Mo=2.00-3.00, Ti=5×C-0.70, Fe=Balance
Mechanical Properties (Annealed)	Tensile Strength ≥515MPa, Yield Strength ≥205MPa, Elongation ≥40%, Hardness ≤217HB	Tensile Strength ≥515MPa, Yield Strength ≥205MPa, Elongation ≥40%, Hardness ≤217HB
Service Temperature	500℃ to 870℃ (continuous service)	400℃ to 900℃ (continuous service)
Equivalent Grades	SUS316H (JIS), EN 1.4407, UNS S31609	SUS316Ti (JIS), EN 1.4571, UNS S31635

Key Performance Differences: 1. High-temperature strength: 316H has higher creep strength than 316Ti at 500-870℃, creep rupture life 1.5-2 times that of 316Ti. 2. Intergranular corrosion resistance: 316Ti forms TiC through titanium, preventing chromium carbide precipitation, with better intergranular corrosion resistance than 316H; 316H needs to control welding heat input to avoid intergranular corrosion. 3. High-temperature stability: 316Ti can work at 900℃ for a short time, 30℃ higher than 316H.

Applicable Scenario Distinction: 316H is suitable for high-temperature stress-bearing components in corrosive environments, such as thermal power plant boiler superheater tubes (coastal areas), high-temperature chemical reactor internals (500-700℃), and high-temperature fan blades. 316Ti is suitable for high-temperature components requiring long-term anti-intergranular corrosion, such as petrochemical cracking furnace tubes, nuclear power plant heat exchanger tubes, and high-temperature pipelines with frequent welding.

Practical Q&A

Q1: What is the core difference between 316H and 316Ti in high-temperature applications? A1: 316H focuses on high-temperature creep strength, suitable for dynamic stress-bearing components; 316Ti focuses on intergranular corrosion resistance, suitable for static components in long-term high-temperature and corrosive environments.

Q2: Can 316H be used in sulfur-containing high-temperature environments? A2: Yes. Molybdenum forms a stable MoS₂ film, inhibiting sulfur corrosion; 316Ti also has this performance, but 316H is more cost-effective for stress-bearing components.

Q3: What welding precautions are there for 316Ti? A3: Titanium is prone to burnout at high temperatures; use TIG welding with pure argon protection, control arc residence time, and select ER316Ti welding wire to ensure titanium content in the weld.

Q4: Which is more expensive between 316H and 316Ti? A4: 316Ti is 15-20% more expensive than 316H, mainly due to the addition of titanium and stricter composition control.

Q5: How to select between 316H and 316Ti for high-temperature pipelines? A5: Choose 316H if the pipeline bears high pressure and dynamic load (temperature ≤870℃); choose 316Ti if the pipeline has many welds, works in 400-900℃ for a long time, or requires high intergranular corrosion resistance.