Stainless steel groups and chemical composition（ISO 3506-12020）

Chemical composition (cast analysisi, mass fraction in %)

A1	Austenitic
A2
A3
A4
A5
A8
C1	Martensitic
C3
C4
F1	Ferritic
D2	Austenitic-Ferritic
D4
D6
D8

0.12	1.00	6.5	0.020	0.15~0.35	16.0~19.0
0.10	1.00	2.00	0.050	0.030	15.0~20.0
0.08	1.00	2.00	0.045	0.030	17.0~19.0
0.08	1.00	2.00	0.045	0.030	16.0~18.5
0.08	1.00	2.00	0.045	0.030	16.0~18.5
0.030	1.00	2.00	0.040	0.030	19.0~22.0
0.09~0.15	1.00	1.00	0.050	0.030	11.5~14.0
0.17~0.25	1.00	1.00	0.040	0.030	16.0~18.0
0.08~0.15	1.00	1.50	0.060	0.15~0.35	12.0~14.0
0.08	1.00	1.00	0.040	0.030	15.0~18.0
0.040	1.00	6.00	0.04	0.030	19.0~24.0
0.040	1.00	6.00	0.040	0.030	21.0~25.0
0.030	1.00	2.00	0.040	0.015	21.0~23.0
0.030	1.00	2.00	0.035	0.015	24.0~26.0

Chemical composition (cast analysisi, mass fraction in %)

A1	Austenitic
A2
A3
A4
A5
A8
C1	Martensitic
C3
C4
F1	Ferritic
D2	Austenitic-Ferritic
D4
D6
D8

0.70	5.0~10.0	1.75~2.25	/	c,d,e
/ f	8.0~19.0	4.0	/	g,h
/ f	9.0~12.0	1.00	/	5C≤Ti≤0.80 and/or 10C≤Nb≤1.00
2.00~3.00	10.0~15.0	4.00	/	h,i
2.00~3.00	10.5~14.0	1.00	/	5C≤Ti≤0.80 and/or 10C≤Nb≤1.00 i
6.0~7.0	17.5~26.0	1.50	/	/
/	1.00	/	/	i
/	1.50~2.50	/	/	/
0.60	1.00	/	/	c,i
/ f	1.00	/	/	j
0.10~1.00	1.50~5.5	3.00	0.05~0.20	Cr+3.3Mo+16N≤24.0 k
0.10~2.00	1.00~5.5	3.00	0.05~0.30	24.0＜Cr+3.3Mo+16N k
2.5~3.5	4.5~6.5	/	0.08~0.35	/
3.00~4.5	6.0~8.0	2.50	0.20~0.35	W≤1.00

a. All values are maximum values except those indicated.b. In case of dispute D. applies for product analysis D. applies for(3) Selenium can be used instead of sulfur, but its use may be limited.d. If the mass fraction of nickel is less than 8%, the minimum mass fraction of manganese must be 5%.

e. When the mass fraction of nickel is greater than 8%, the minimum copper content is not limited.

f. Molybdenum content may appear in the manufacturer’s instructions. However, for certain applications, if it is necessary to limit the molybdenum content, it must be indicated by the user in the order form.

④, g. If the mass fraction of chromium is less than 17%, the minimum mass fraction of nickel should be 12%.

h. Austenitic stainless steel with a mass fraction of 0.03% carbon and a mass fraction of 0.22% nitrogen.

⑤, i. For larger diameter products, the manufacturer’s instructions may contain a higher carbon content to achieve the required mechanical properties, but it should not exceed 0.12% for Austenitic steel.

⑥, j. Titanium and/or niobium may be included to improve corrosion resistance.

⑦, k. This formula is used solely for the purpose of classifying duplex steels in accordance with this document (it is not intended to be used as a selection criterion for corrosion resistance).

Post time: Dec-13-2022