UNS N10276 C276 Seamless Nickel Alloy Pipe ASTM B622 Solution Annealed for Corrosion Resistance

UNS N10276 Alloy C276 seamless nickel alloy pipe is a Ni-Cr-Mo-W corrosion-resistant tubular product designed for highly aggressive chemical and refinery environments. Its nominal alloy system combines approximately 14.5-16.5% chromium, 15.0-17.0% molybdenum and 3.0-4.5% tungsten with nickel as the balance.

For seamless pipe and tube, ASTM B622 is the primary product specification. In the solution-annealed condition, UNS N10276 requires a minimum tensile strength of 690 MPa, minimum 0.2% offset yield strength of 283 MPa and minimum elongation of 40%.

The low carbon and silicon limits of C276 reduce carbide and intermetallic precipitation during thermal processing and welding. This makes the alloy suitable for equipment exposed to mixed oxidizing and reducing media, chlorides, sulfur-bearing process streams and acidic refinery environments.

• High Resistance to Localized Corrosion: The combination of 15.0-17.0% Mo and 3.0-4.5% W gives C276 strong resistance to pitting and crevice corrosion in chloride-containing process environments.
• Controlled Low Carbon Content: Carbon is limited to 0.010% maximum and silicon to 0.08% maximum, restricting detrimental grain-boundary precipitation during fabrication.
• High Room-Temperature Strength: ASTM B622 requires minimum tensile strength of 690 MPa, 0.2% yield strength of 283 MPa, and elongation of 40%.
• Broad Chemical Compatibility: Suitable for hydrochloric acid, sulfur-containing compounds, chloride-bearing solutions, and mixed oxidizing/reducing chemical conditions.
• Excellent Weldability: Low carbon and silicon composition permits conventional welding methods with reduced susceptibility to grain-boundary carbide precipitation.

• Verified Alloy Identity and Heat Traceability: Complete traceability from raw material through finished pipe with positive material identification and mill certificates.
• Controlled Solution Annealing: Proper thermal processing with temperature control and heat-treatment records maintained for each production batch.
• Comprehensive Testing: Dimensional measurement, visual examination, tensile testing, hydrostatic testing, and applicable nondestructive electric testing.