C276 (UNS N10276) is a cold hardened nickel-based alloy intended for the most extreme well conditions up to 450°F.
In addition to its exceptional corrosion resistance under the most severe conditions, higher strengths may be achieved with C276 than other nickel alloys. It is therefore used for downhole tubular components, packers, and other subsurface equipment under the most extreme environmental conditions found in high-pressure, high-temperature (HPHT) wells, saltwater Injection wells, and Acid Gas Injection (AGI) wells. However, all environmental factors, including H2S, CO2 , temperature, pH, and chloride concentration, should be considered before final material selection.
The alloy is classified in MR0175/ISO15156 as a type 4e alloy, with no restrictions to a partial pressure of H2S below 400°F and resistant to 1000 psi H2S at 450°F.
14.5 - 16.5
4 - 7
15 - 17
3 - 4.5
Made by electric furnace process or blast furnace followed by Vacuum Oxygen Decarburization (VOD) process or Argon Oxygen Decarburization (AOD) Process
Manufactured by traditional tube manufacturing processes, High strength tubulars should be furnished in cold worked condition
Solution Annealing Process before final cold drawing
Specified Mechanical Properties
API 5CRA / ISO 13680 Group 2 Category 15-60-16
Yield Strength ksi
Tensile Strength ksi
NACE MR0175/ISO 15156 H2S Sour Service Limits
No limit ≤ 400°F, Refer to table for temperatures up to 450°F
140 Grade not recommended for sour service
*Non-standard mechanical properties and grades are made available upon agreement.