Martensitic Stainless Steels

Martensitic Stainless Steels

Martensitic stainless steels are the first branch of the plain chromium stainless steels.

The common grades are 410, 416, 420/420C, 431 and 440C these are all alloys containing iron, chromium (12% to 18%) and carbon (up to 1%). These steels are able to be hardened by way of a quench and temper heat treatment process and capable of high levels of strength and hardness.

The basic characteristics of martensitic stainless steels are that they have low resistance too high and low temperature, moderate corrosion resistance. Are magnetic with low ductility along with a medium work hardening rate. Can be welded providing correct procedures are followed but commonly used in machining applications.

Typical applications for the use of Martensitic stainless steels include Knife blades, domestic cutlery, surgical instruments, special fasteners, turbines, impellers, valve bodies and chemical engineering equipment. Most commonly supplied in bar form with options of sheet, plate and coil predominantly in Grade 420/420C for blade manufacture.

Grade and Typical application:

410 – General purpose used for nuts, bolts, bushings, pump and valve parts in mildly corrosive environments.

416 – Free machining variation of 410 used in the same applications.

420 – General use, pump shafts and valve assemblies.

420C – Created to obtain high hardness after heat treatment for tooling and Blade manufacture.

431 – Hardenable steel with corrosion resistance close to 304, ideal for pump shafts, beater bars and marine hardware applications.

440C – Highest hardness and abrasion resistance of all the stainless steels used in valve seats, surgical equipment and bearings.

Welding

Grade
EN #
AISI #
UNS #
EN Name
AWS Class.
X134/EL
1.4313
-
S41500
X3CRNIM013-4
-

Precipitation Hardening

These steels with a minimum of 10.5% Cr have exceptional strength due to heat treatment at various temperatures that induces precipitation hardening (also known as aging). This process allows a sub microscopic precipitation of phase rich in elements coherent with the matrix (for example Cu ) that greatly increases the mechanical properties of the steel.

Grade
EN #
AISI #
UNS #
EN Name
V157M
1.4574
632
S15700
-
V145
-
XM-25
S45000
-
V145/1
1.4594
-
-
X5CRNIM0CUNB14-5
V155
1.4545
XM-12
S15500
-
V174
1.4542
630
S17400
X5CRNICUNB16-4
V174/1
1.4548
630
S17400
X5CRNICUNB17-4-4
V174LC*
1.4542
630
S17400
X5CRNICUNB16-4
V176T
-
635
S17600
-
* For load cells or higher Rp02/Rm ratio.

Grades

Grade
EN #
AISI #
UNS #
EN Name
BS #
CMXA
-
440A
S44002
-
-
CMXB
-
440B
S44003
-
-
CMXBM
1.4112
-
-
X90CRM0V18
-
CMXC
1.4125
440C
S44004
X105CRM017
-
CMXC/1
-
440C
S44004
-
-
CMX/DE
1.4037
-
-
X65CR13
-
VAL1
1.4006/1.4011
403/410
S40300/S41000
X12CR13/X12CR12
410S21
VAL1AL/2
1.4002
405
S40500
X6CRAL13
-
VAL1B/DE
1.4024
-
-
X15CR13
-
VAL1HS
1.4005
416
S41600
X12CRS13
416S21
VAL1PT
1.4512
409
S40900
X2CRTI12
-
VAL1Z
1.4005
416
S41600
X12CRS13
416S21
VAL2A
1.4021
420
S42000
X20CR13
-
VAL2AM
1.4120
-
-
X20CRM013
-
VAL2A/UK
-
-
-
-
420S29
VAL2A/UK2
-
-
-
-
420S37
VAL2B
1.4028
420
S42000
X30CR13
420S45
VAL2C
1.4031
420
S42000
X39CR13
-
VAL2CZ
1.4035
-
-
X45CRS13
-
VAL2D
1.4116
-
-
X50CRM0V15
-
VAL2/DE
1.4034
-
-
X46CR13
-
VAL2/DS
1.4036
-
-
X46CRS13
-
VAL2BZ
1.4029
420F
S42020
X29CRS13
-
VAL3
1.4122
-
-
X39CRM017-1
-
VAL3S
1.4122
-
-
X35CRM017
-
VAL4
1.4057
431
S43100
X17CRNI16-2
-
VAL4/UK
-
-
-
-
431S29
X134M
1.4313
-
S41500
X3CRNIM013-4
-
X134M/1
1.4313/1.4413
-
S41500
X3CRNIM013-4/X4CRNIM013-4
-
X134M/3
-
-
S41500
-
-
X164M
1.4418
-
-
X4CRNIM016-5-1
-