AISI 444 is a low carbon, dual stabilised, molybdenum containing ferritic stainless steel with good ductility, toughness and resistance to sensitisation, even in the welds. With 18% chromium and 2% molybdenum, the steel has good pitting resistance and crevice corrosion resistance, similar to CS316 and good general corrosion resistance and oxidation resistance, similar to 316 in most environments. Being a ferritic stainless steel, AISI 444 is not susceptible to Stress Corrosion Cracking. Annealed AISI 444 is ductile and can be formed using a wide range of roll forming or mild stretch bending operations as well as the more common drawing and bending operations. AISI 444 does not harden excessively during cold working.

Characteristics

> Excellent resistance to chloride pitting and crevice corrosion cracking

> Immune to Chloride ion stress corrosion

> Maintains high strength at elevated temperatures

> Resistant to sea water, in both flowing and stagnant condition

>Heat resistant

Applications

> Marine engineering

> Furnaces a gas turbines

>Chemical processing plants

> Boiler a pressure vessels

> Nuclear power plants

Equivalent

Euronorm	Nom.	AISI / ASTM / UNS
1.4521	X2CrMoTi18-2	444

Chemical Composition

Type	C	Mn	Si	P	S	Cr	Mo	Ni	Nb	Ti
444	0.025 max	1.00 max	1.00 max	0.040 max	0.030 max	71.5-19.50	1.75-2.50	1	1	0.20+4(C+N) 0.80

Mechanical Properties

Type	Product Form	0.2% Proof Stress (Mpa)	Tenstile Strength (Mpa)	Elongation (%)	Brinell Hardness
444	C	275 min	415 min	20 min	217

Delivery Condition

Stress Relieved Annealed

Bright Annealed

Normalized

Solution Treatment

Sizes

Hot Rolled Process – OD 30-500mm ; WT 3-60mm ; L 6-12meter

Cold Drawn Process – OD 10-200mm ; WT 0.5-20mm ; L 1-12meter

Cold Rolled Process – OD 6-200mm ; WT 0.1-20mm ; L 1-12meter

Surface

Acid pickling – pre-passivation process of treating stainless steel parts with an acid solution, typically hydrochloric or sulfuric acid, which can remove oxide scale and heat tint while dissolving steel flecks embedded in the part.

Polishing – P grade sandpaper: P150, P200, P250, P300, P400, P500, P600, P700, P800

Inspection

Chamical analysis / Tensile test at room temperature / flattening test / ring tensile test / drift expemdomg test / ring expanding test / leak tightness test / Tensile test at elevated temperature / impact test at room temperature / impact test at low temperature / eddy current test / ultrasonic test / magnetic flux leakage test

CORROSION RESISTANCE

Type 444 provides excellent corrosion resistance in moderately severe environments of many types that include chlorides and organic acids found in foods and beverages. It also provides satisfactory resistance to dilute sulfuric acid solutions and to highly concentrated sodium hydroxide.

FORMABILITY

Type 444 provides excellent formability and can be readily deep drawn and spin formed. Stretch forming, however, is limited in application for this material.

WELDABILITY

The ferritic class of stainless steels is generally considered to be weldable by the common fusion and resistance techniques.