1. What is the chemical composition of Hastelloy C-276 (UNS N10276)?
Answer:
Hastelloy C-276 is a nickel-molybdenum-chromium alloy.
Typical composition: Ni ~57%, Cr ~16%, Mo ~16%, Fe ~5%, W ~3%, with minor Co, Mn, and C.
The alloy is specially formulated for superior resistance to pitting, stress corrosion cracking, and oxidizing/reducing acids.
2. What are the typical applications for Hastelloy C-276 pipes and tubes?
Answer:
Chemical processing: handling strong acids such as hydrochloric, sulfuric, and nitric acids.
Marine and desalination systems: resistant to seawater corrosion.
Pollution control and pharmaceutical industries: for piping systems and reactors exposed to corrosive chemicals.
Industrial equipment: heat exchangers, tanks, and vessels operating in aggressive environments.
3. What temperature and environmental conditions can Hastelloy C-276 withstand?
Answer:
Continuous service up to approximately 450–500°C depending on environment.
Excellent resistance to oxidizing and reducing conditions including hot chlorides and strong acids.
Can be used in highly corrosive, wet, and oxidizing/reducing environments without significant degradation.
4. What forms, sizes, and finishes are available for Hastelloy C-276?
Answer:
Forms: Seamless pipes, welded pipes, and precision tubes.
Sizes: Standard diameters range from 1/2" to 24" (DN 15–DN 600), with wall thicknesses per ASTM B622/B619 standards. Custom sizes available.
Finishes: Hot-rolled, cold-rolled, polished, or solution-annealed for corrosion resistance.
Lengths: Random or cut-to-length as per customer requirements.
5. What quality assurance and testing are provided for Hastelloy C-276 pipes/tubes?
Answer:
Chemical analysis: Spectrometer or optical emission testing to verify alloy composition.
Mechanical testing: Tensile, yield, elongation, and hardness tests.
Non-destructive testing (NDT): Ultrasonic, eddy current, or dye-penetrant inspection to detect defects.
Heat treatment verification: Solution annealed or annealed/aged as per customer requirements.
Documentation: Mill Test Certificates (MTC), traceability, and compliance with ASTM, ASME, or customer specifications.
