Composition and properties

Steel AISI 444 (1.4521) complies with standard specifications EN 10088-2:2005 (for EU countries) and ASTM A 240-08 (for USA). It contains the following chemical elements:

Due to the reduced carbon content, the steel has a purely ferritic structure when rolled. During primary heat treatment - annealing - AISI 444 steel (1.4521) shows weak ferromagnetic properties. The alloy is characterized by the density of 7.7 ^g/cm3 and has a low coefficient of thermal expansion: in the temperature range from 20 to¹⁰⁰⁰ C it is only 10.^4x10-6 1/K. This material is also characterized by high thermal conductivity, which is fully preserved within the temperature range of 20...²⁰⁰⁰ C. The thermal conductivity coefficient is 23 W/mK and the modulus of elasticity is 220 GPa.

A distinctive feature of steel AISI 444 (1.4521) is its high corrosion resistance, which is preserved even in the simultaneous presence of particularly active gaseous media, which cause corrosion - vapors of hydrochloric and sulfuric acids. According to these characteristics, the alloy is almost identical to acidic austenitic steels, in particular AISI 316 (1.4404), melting of which is much more expensive economically. At the same time under prolonged exposure to high temperatures and high concentrations of aggressive vapors on the inner surface of the pipes pitting-corrosion may occur. This should be taken into account when using this steel as a material for gas and pipelines.

Application of

Pipes, rounds and wires made from this alloy are produced using traditional cold and/or hot rolling methods. The advantage of this steel (in comparison to AISI 444 steel, for example) is that it is less dependent on the accuracy of the hardening process. This allows customers to reduce their ongoing operating costs.

A distinctive feature of the alloy in question is its two-component stabilization, which is produced by the combined action of niobium and titanium in the melting process. Therefore AISI 444 (1.4521) steel can be processed on metal cutting and deforming equipment in cold and hot condition. Wires and rounds of this alloy can be drawn with considerable degrees of deformation, and can be cold drawn on automatic multi-position machines to produce fasteners. Welding conditions do not differ from other materials of a similar class.

Pipes made of AISI 444 (1.4521) steel are used in the manufacture of pipelines pumping chemically active media, which may be accompanied by intense corrosive phenomena. Circle and wire of this alloy are used in the manufacture of precision parts of control and measuring instruments in the pharmaceutical, chemical and metallurgical industries.

Domestic metallurgy produces 02X18M2BT alloy, which by its composition does not practically differ from steel AISI 444 (1.4521).

Pipes, rounds and wires made of AISI 444 (1.4521) steel offered for sale by Evek GmbH are one hundred percent quality guarantee, which is confirmed by certificates attached to each batch of rolled products.