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SOLUTIONS: Stainless Steel Martensitic Stainless Steel This steel, also in the AISI 400 series, is the iron chromium alloys capable of being heat treated to a wide range of hardness and strength levels. Chromium content is lower and carbon content higher than the ferritic group. These grades are magnetic

AISI

Type

in all conditions. They are not as corrosion resistant as the austenitic and ferritic types. Martensitic grades are used to resist abrasion in stream and gas turbine components and for such applications as bearings, ball bearings, pump shafts etc.

Composition % *

Carbon C

Chromium Cr

Other

403 410 414

0,15 0,15 0,15

11,5 – 13,0 11,5 – 13,5 11,5 – 13,5

0.5 Si

– 1.25 – 2.5 Ni

416 416Se 420

0,15 0,15 0,15 min.

12,0 – 4,0 12,0 – 14,0

12,0 – 14,0

1.25 Mn, 0.15 S, (min.), 0.060 P, 0.60 Mo (opt)

1.25 Mn, 0.060P, 0.15 Se (min.)

–

422 0,2 – 0,25 11,0 – 13,0

431 0,20 15,0 – 17,0

440A

0,60 – 0,75 16,0 – 18,0

440B

0,75 – 0,95 16,0 – 18,0

440C

0,95 – 1,20 16,0 – 18,0

1.0 Mn, 0.5 – 10.0 Ni, 0.75 Si, 0.75 – 1.25 Mo,

0.75 _ 1.25 W, 0.15 – 0.3 V, 0.025 P, 0.025 S 1.25 – 2.5 Ni

0.75 Mo

0.75 Mo

0.75 Mo

May be welded with (E) Electrode (W) Wire Welding

2.06

23/14-322N (E)

S-309-M-GF-222 (W)

Non-weldable

* Single values denote maximum percentage unless otherwise noted. + Unless otherwise noted, other elements of all alloys listed include maximum contents of 1.0 % Mn, 1.0% Si, 0.040% P, and 0.030% S. Balance is Fe.

Martensitic stainless steel, has the following characteristics: • Magnetic.

• Can be hardened by heat treatment. • Poor welding characteristics. • Grade: 410 (most used), 440C (for very high hardness). • Unified numbering system UNS: S 41000, S 42000, S 44004.

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