Fermonic 60 (UNS S21800)

Description:

Fermonic® 60 is a fully austenitic alloy supplied in the hot worked and annealed condition. The general corrosion resistance is between that of Alloy 304 and Alloy 316 stainless steel, whereby is it generally better than Alloy 304 in most environments but superior to Alloy 316 with respect to chloride pitting resistance. More significantly, additions of Silicon and Manganese provide superior wear, galling and fretting resistance than many other corrosion resistant alloys making it preferable for applications where there is repeated movement/sliding or frequent assembly/disassembly.

These compositional additions also provide almost double the yield strength of Alloys 304/316, and higher strength can be achieved through cold working. Importantly, it remains fully austenitic – and therefore, fully non-magnetic – even after severe cold-working, although there is no improvement in galling performance from this operation.

Key Features:

  • Superior resistance to galling and associated wear mechanisms
  • Retention of mechanical properties up to 1200°C combined with good oxidation resistance
  • Good corrosion resistance in a wide variety of environments
  • Cost effective alternative to Cobalt- and Nickel-based alloys in wear/galling critical applications
  • Readily strengthened by cold-working
  • Non-magnetic
  • Readily fabricated and welded in the same way as Alloy 304/316

Applications:

  • Fasteners
  • Pins and bushings
  • Wear rails and guides
  • Roller bearings
  • Marine shafts
  • Pump components such as seals and wear rings
  • Valve stems, seats and trim

Chemical Composition:

Cr Ni Mo Co Nb (+Ta) Ti W Cu C Mn N Si P S Fe Al
Min 16.00 8.00 0.06 7.50 0.10 3.70
Max 17.00 8.50 0.75 0.10 0.05 0.15 0.75 0.08 8.50 0.18 4.20 0.040 0.030 Bal 0.02

Mechanical Properties:

Bars up to and including 0.5” diameter or section Bars above 0.5” diameter or section
0.2% Proof Stress 379 N/mm2 55ksi 345 N/mm2 50ksi
Tensile Strength 724 N/mm2 105ksi 655 N/mm2 95ksi
Elongation, 5.65√S0 and 4D 35% 35%
Reduction of Area 55% 55%
Hardness (Brinell) 241 max 241 max

Notes:

  1. Tensile testing shall be carried out in accordance with ASTM A370 or EN10002-1
  2. Minimum properties quoted (tested at room temperature in a longitudinal direction)
  3. Testing performed on each melt of material per heat treatment batch

Physical Properties:

Density (Kg/m3) 7622
Magnetic Permeability (20°C) 1.003
Young’s Modulus (kN/mm2) 181
Specific Electrical Resistance, 20°C (Ω-m) 0.98 x 10-6
Mean coefficient of thermal expansion, 20-100°C (m/m/°C) 15.8 x 10-6

Downloads

Datasheet - S-Fermonic 60 (Alloy 218)

Datasheet - S-Fermonic 60 (Alloy 218)