Ferralium® 255 is a super duplex stainless steel supplied in the cold finished and annealed condition. As a 25% Chromium alloy, with significant additions of Copper, 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.
In its various product forms, Ferralium® 255 is listed in NACE MR 0175 for sour service and gained ASME Approval for Pressure Vessel applications. It has been tested to the highest degree using tests designed to guarantee that the trade-marked product possesses high integrity, a correct phase balance and the absence of sigma and other deleterious phases.
|0.2% Proof Stress||550 N/mm2||80 ksi|
|Tensile Strength||760 N/mm2||110 ksi|
|Elongation, 5.65√S0 and 4D||15%|
|Reduction of Area|
|Hardness (Rockwell C)||28 HRC max.|
– Hydrostatic Pressure Test of ASTM A999/A999M
– Non-Destructive Test of ASTM E213 or ASTM E309
– Flattening Test requirements of ASTM A999/A999M
|Magnetic Permeability (20°C)||33|
|Young’s Modulus (kN/mm2)||199|
|Specific Electrical Resistance, 20°C (Ω-m)||0.80 x 10-6|
|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|