Stainless Steel

Classified according to the following categories:

• Ferritic stainless steels are magnetic and nickel free.  They consist of an iron/chrome alloy.
• Austenitic stainless steels are not magnetic and extremely diverse.  They contain nickel, ca 17% chrome, molybdenum, titanium or niobium additives.
• Austenitic-ferritic steels are magnetic and also described as Duplex Steels.

Composition

Stainless Steels	Composition (average)						PRE- Value	Temp.- Resistance in °C
	%C max.	%N max.	% Cr	% Ni	% Mo	others
Ferritic
1.4016 (AISI 430)	0.04		16.5				16.5
1.4521 (AISI 444)	0.025		17.5		1.9	0.7%Ti	24
Austenitic
1.4301 (AISI 304)	0.04	0.1	18	9			20	450
1.4306-07 (AISI 304L)	0.02	0.1	19	9			21	450
1.4401 (AISI 316)	0.04	0.1	17	11	2		25	450
1.4404 (AISI 316L)	0.02	0.1	17	11	2		25	450
1.4435	0.03	0.1	18	14	2.5		28	450
1.4539 (AISI 904L)	0.01		20	25	4.3	1.5%Cu	35	500
1.4541 (AISI 321)	0.08	0.1	18	11		0.7%Ti	20	450
1.4547	0.02	0.2	20	18	6.5	Cu	43	500
1.4550 (AISI 347)	0.08	0.04	17.5	9.5		Nb	18	450
1.4571 (AISI 316 TI)	0.08	0.1	17	12	2.5	0.7%Ti	26	450
1.4841 (AISI 310)	0.2	0.1	25	20			26	1100
1.4864 (AISI 330)	0.05	0.1	17	36			19	1050
1.4893	0.1	0.17	21	11		Ce	24	1100
Duplex
1.4462 (AISI 318 LN)	0.02	0.17	22	5.7	3.1		34

Corrosion resistant alloys
Heat resistant alloys

The PRE-Value allows comparison of different anticorrosive steels with regard to the Pitting Resistance Equivalent.

PRE-value = %Cr + 3.3%Mo + 16%N

Steels with a PRE-value of over 33 are resistant to attack by seawater.

This table is intended to give an overview of the different material values and is not a comprehensive list.  It does not give all information on material composition.