Stainless Steel and Duplex

STAINLESS STEEL

Austenitic steels are iron-based FCC steels with

16-25% Cr (the Cr is incorporated such that a self-healing CEO Chromium(II) oxide forms at the surface); Mo, which enhances resistance to pitting; and Ni, which produces austenite.

Austenitic steels have higher strength and better corrosion and oxidation resistance than Ferritic and Martensitic stainless steels. They are, however, limited by swelling resistance under radiation and have some susceptibility to stress-corrosion cracking in water-cooled nuclear systems. In fact, in fusion, and light water reactor environments, void swelling occurs in austenitic steels, which leads to a loss of ductility. This is due to “quasi-embrittlement,” where there is a suppression of uniform deformation. In this case, macroscopically the alloy appears to soften although the ductility decreases dramatically due to the microscopic deformation in the region of failure.

Austenitic steels limit the desired high burn-up range due to low resistance to radiation-induced swelling. Even at moderate neutron doses, they encounter a substantial amount of void swelling, which is far higher than that found in Ferritic and Martensitic stainless steels.

Duplex SS are two-phase alloys containing an equal proportion of ferritic and austenitic phases in their microstructure, providing a combination of the corrosion resistance of austenitic stainless steels with enhanced strength. Hence, they have a mixed microstructure of austenite and ferrite, the aim usually being to produce a 50/50 mix, although in commercial alloys the ratio may be 40/60. With carbon content lower than 0.03%, the amount of Cr and Ni content can be varied from 20% to 30% and from 5% to 8%, respectively. Minor alloying elements contained in duplex SS include molybdenum, nitrogen, tungsten, and copper.

The most commonly used stainless steel and duplex of Metalworldtop supplying is AISI 316Ti, AISI 347, 2205, and 2507 steel in several forms and specifications. These include pipe, tubing, bars, and pipe flanges solution-treated and quenched materials, these materials are widely used in the oil and gas industry, marine industry, chemical processing, and nuclear industries for their excellent strength.

Area of applications

Shipbuilding, chemical, dyeing, brewing, offshore, pharmaceutical, textile, petrochemical, plastics, and paper industries use stainless steel.

Bolts, nuts that work with salts, ships and ship components, medical implants, surgical implants, springs, oil and gas pipelines, heat exchangers, fittings, and installation components.

Construction| Balustrades, frames, ornaments, welded fittings, installations, rubber-producing machine parts.

Material Corresponding