What alloy materials are available for metal expansion bellows?

1. Austenitic Stainless Steels (Standard & Heat-Resistant)

• 304 / 304L (SA240)
  • General-purpose, good corrosion resistance, cost-effective
  • Max temp: ~300–425°C
  • Water, air, neutral gases, low-corrosion industrial systems
• 316 / 316L (SA240)
  • Better chloride/pitting resistance than 304
  • Food, pharmaceuticals, marine, chemical processing
• 321 (1.4541) / 316Ti (1.4571)
  • Stabilized against sensitization; good up to ~600°C
  • High-temperature steam, flue gas, thermal cycling
• 310S (2520)
  • High heat resistance (~900°C), oxidation resistance
  • High-temperature flue gas, furnace ducts

2. Duplex & Super Austenitic Stainless Steels

• 2205 (S31803)
  • High strength, excellent stress–corrosion cracking (SCC) resistance
  • Chloride-rich environments, brackish water, oil/gas
• 254SMO / 904L / AL6XN
  • Super corrosion resistance to acids, halides, strong chemicals
  • Seawater, sulfuric acid, phosphoric acid, aggressive chemicals

3. Nickel–Based Alloys

• Monel 400 / K500
  • Ni–Cu alloy; excellent seawater/steam corrosion resistance
  • Marine, saltwater, chemical processing

• High temperature (~650–1090°C), creep, oxidation, corrosion
• Power, aerospace, high-temperature flue gas, petrochemical
  • Incoloy 800 / 800H / 800HT / 825
    • Good high-temperature strength and corrosion resistance
    • Heat exchangers, furnace parts, chemical processing
  • Hastelloy C‑276 / C‑22 / B‑3
    • Extreme corrosion resistance to acids, halides, reducing/oxidizing media
    • Strong acids (HCl, H2SO4), corrosive chemicals, waste treatment
• 4. Copper Alloys

  • Brass / Bronze
    • Low cost, good formability, moderate corrosion
    • HVAC, general-purpose low-corrosion systems
    • Beryllium Copper (BeCu)
      • High strength, fatigue life, electrical conductivity
      • Aerospace, instrumentation, high-cycle applications

    • 5. Titanium & Titanium Alloys (GR1, GR2, TA1, TA2)

      • Excellent corrosion resistance (especially seawater, oxidizing acids), low density
      • Marine, chemical, offshore, high-purity systems

      6. Special Alloys

      • Pure Nickel (Ni200 / Ni201 / N4 / N6)
        • Excellent corrosion in reducing environments
        • Caustic, chemical processing
      • Tantalum, Zirconium
        • Extreme corrosion resistance in highly aggressive media
        • Specialty chemical, pharmaceutical, nuclear applications

      Summary of Selection

      • General service: 304 / 316
      • Chlorides/seawater: 316L / 2205 / 254SMO
      • High temperature: 321 / 310S / Inconel / Incoloy
      • Strong acids/corrosion: Hastelloy / Titanium
      • Marine/steam: Monel