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.


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.

  • Martensitic Stainless Steel
  • Martensitic Stainless Steel
  • Martensitic Stainless Steel
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/
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/
S41500 X3CRNIM013-4/
X134M/3 S41500
X164M 1.4418 X4CRNIM016-5-1