Ferralium 255 – 3SC for Castings (UNS S32550)


Ferralium® 255 – 3SC is a super duplex stainless steel supplied in cast form. As a 25% Cr alloy, with significant additions of Cu, it offers excellent corrosion resistance in a wide variety of corrosive chemicals including sulphuric, nitric and phosphoric acid.

In seawater and other chloride containing environments it also provides outstanding resistance to pitting and crevice corrosion, with Critical Pitting Temperature exceeding 50°C. Excellent ductility and impact strength at both ambient and sub-zero temperatures combine with a high resistance to abrasion, erosion and cavitation erosion.

Chemical Composition:

Cr Ni Mo Co Nb (+Ta) Ti V W Cu C Mn N Si P S Fe Al
Min 24.00 5.50 2.70 1.00 0.14
Max 26.00 7.50 3.90 2.00 0.025 2.00 0.25 0.70 0.035 0.010 Balance

Mechanical Properties:

0.2% Proof Stress 450 N/mm2 65.3 ksi
Tensile Strength 700 N/mm2 101.5 ksi
Elongation, 5.65√S0 and 4D 25%
Reduction of Area
Hardness (Brinell) 270 max
Impact Strength (Room Temp) 70J 51.6 ft.lb


  1. Testing shall be carried out in accordance with ASTM A370 or EN ISO 6892-1 (tensile), EN ISO 6506-1 (hardness)
  2. Minimum properties quoted (tested at room temperature in a longitudinal direction)
  3. Testing performed on each melt of material per heat treatment batch
  4. ASTM G48A corrosion test (at 50°C) no pitting and < 0.8g/m2 weight loss
  5. Ferrite content  40-60%
  6. Microstructure certified free from grain boundary carbides, sigma, chi and laves phases





Physical Properties:

Density (Kg/m3) 7810
Magnetic Permeability (20°C) 33
Young’s Modulus (kN/mm2) 199
Specific Electrical Resistance, 20°C (µΩ-m) 0.8
Mean coefficient of thermal expansion, 20-100°C (m/m/degC) 11.1 x 10-6
Specific Heat, 20°C (J/kg.K) 475
Thermal conductivity, 20°C (W/m.K) 14.2
Fracture Toughness, KQ (MPa/m2) 98


Datasheet - SD-Ferralium 255 3SC Castings

Datasheet - SD-Ferralium 255 3SC Castings

Brochure - Ferralium 255-SD50 - Detailed product information

Brochure - Ferralium 255-SD50 - Detailed product information