Ferralium® 255 – FG46 is a super duplex stainless steel which is supplied in the strain hardened condition (Condition S). It is optimised for fastener applications, matching the mechanical properties of the B7 grade alloy carbon steel which is most commonly used for high-pressure bolting applications.
As a variant of our unique Ferralium® 255 – SD50 product, it is a 25% Cr alloy with significant additions of Cu, delivering excellent corrosion resistance in a variety of corrosive chemicals including sulphuric, nitric and phosphoric acid.
In seawater and other chloride containing environments it also provides outstanding long term resistance to pitting and crevice corrosion, with a critical pitting temperature exceeding 50°C.
The product retains its excellent ductility and impact strength at both ambient and sub-zero temperatures, despite the elevated strength levels. These are combined with a high resistance to abrasion, erosion and cavitation erosion.
Ferralium® 255-FG46 is 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.
|Bars up to and including 4.0” diameter or section|
|0.2% Proof Stress||720 N/mm2||104.4 ksi|
|Tensile Strength||860 N/mm2||124.7 ksi|
|Elongation, 5.65√S0 and 4D||16%|
|Reduction of Area||50%|
|Impact Strength (Room Temp)||80J||59 ft.lb|
|Impact Strength (-46degC)||45J av (35J min)||33 ft.lb av (25.8 ft.lb min)|
|Magnetic Permeability (20°C)||33|
|Young’s Modulus (kN/mm2)||220|
|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|