Martensitic Stainless Steel

   

Austenitic | Martensitic | Ferritic | Duplex | Super Duplex | Superaustenitic | Superferritic | Precipitation Hardening

Martensitic stainless steel have the highest strength but also the lowest corrosion resistance of the stainless steel. Martensitic steels with high carbon contents are used for tool steel. Due to their high strength in combination with some corrosion resistance, martensitic steel are suitable for applications where the material is subjected to both corrosion and wear. An example is in hydroelectric turbines.

Martensitic grades of stainless steel were developed in order to provide a group of stainless alloys that would be corrosion resistant and hardenable by heat treating. The martensitic grades are straight chromium steels containing no nickel. They are magnetic and can be hardened by heat treating. The martensitic grades are mainly used where hardness, strength, and wear resistance are required.

Martensitic stainless steel has a relatively high carbon content (0.1% – 1.2%) compared to other stainless steel. The martensitic steel are plain chromium steel containing between 12% and 18% chromium, can be heat treated to obtain high strength with good ductility. Martensitic stainless steel has very high hardenability. When only limited corrosion resistance or resistance to moderately elevated temperature scaling is required, can be used in the annealed condition, but its highest corrosion resistance is attained in the hardened and stress relieving (low temperature tempered) condition.

410-Stainless-Steel-Pipe
Type 410Basic martensitic grade, containing the lowest alloy content of the three basic stainless steels (304, 430, and 410). Low cost, general purpose, heat treatable stainless steel. Used widely where corrosion is not severe (air, water, some chemicals, and food acids. Typical applications include highly stressed parts needing the combination of strength and corrosion resistance such as fasteners.
Type 410SContains lower carbon than Type 410, offers improved weldability but lower hardenability. Type 410S is a general purpose corrosion and heat resisting chromium steel recommended for corrosion resisting applications.
Type 414Has nickel added (2%) for improved corrosion resistance. Typical applications include springs and cutlery.
Type 416Contains added phosphorus and sulfur for improved machinability. Typical applications include screw machine parts.
Type 420Contains increased carbon to improve mechanical properties. Typical applications include surgical instruments.
Type 431Contains increased chromium for greater corrosion resistance and good mechanical properties. Typical applications include high strength parts such as valves and pumps.
Type 440Further increases chromium and carbon to improve toughness and corrosion resistance. Typical applications include instruments.

The major alloying addition in martensitic stainless steel is chromium in the range of 11 to 17%. The carbon levels can vary from 0.10 to 0.65% in these alloys. This radically changes the behavior of the martensitic alloys relative to the ferritic 400 Series alloys. The high carbon enables the material to be hardened by heating to a high temperature, followed by rapid cooling (quenching). Martensitic types offer a good combination of corrosion resistance and superior mechanical properties, as produced by heat treatment to develop maximum hardness, strength and resistance to abrasion and erosion. The martensitic grades are usually sold in the soft state. This allows the customers to cut or form the parts before they are thermally hardened. End uses include cutlery, scissors, surgical instruments, wear plates, garbage disposal shredder lugs, and industrial knives. The AL 403 alloy is used to make vanes for steam turbines.

Martensitic / Super Martensitic Grade Comparison Chart:

China GBISO Unified Digital CodeASTMUNS CodeEN CodeCompany Commercial Grade
06Cr13S41008410SS410081.4
12Cr13S41010410S410001.4006
20Cr13S42020420S420001.4021API/13Cr L80
30Cr13S42030420J2S420001.4028
14Cr17Ni2S43110431S43100
05Cr17Ni4Cu4NbS5174017-4PHS174001.4542
06Cr13Ni4MoS415001.4313 F6NM
0Cr16Ni5Mo1N1.4418
00Cr17Ni5Mo2Cu17Cr110/125SM17CRS(NSSMC)

Martensitic Stainless Steel Grades

Alloy
(UNS Designation)
End UseComposition
nominal wt%
SpecificationsDensity
lb/in3 (g/cm³)
Tensile
Strength
ksi. (MPa)
0.2% Yield
Strength
ksi. (MPa)
Elong-
ation %
Hardness
AL 403
S40300
Turbine blades, banding, strapping and hose clampsC 0.15 max, Mn 1.0 max, Si 0.5 max, Cr 11.5-13.0, Ni 0.6 max, P 0.04 max, S 0.03 max, Fe BalanceASTM A176 AMS QQ57630.280
(7.75)
70 min
(485 min)
30 min
(205 min)
25 min96 Rockwell B max
410
S41000
Cutlery, dental and surgical instruments, nozzles, valve parts, hardened steel balls and seats for oil well pumps, separating screens and strainers, springs, shears, and wear surfacesC 0.08-0.15, Mn 1.0 max, P 0.04 max, S 0.03, Si 1.0, Cr 11.5-13.5, Ni 0.75 max, Fe BalanceASTM A2400.276
(7.65)
65 min
(450 min)
30 min
(205 min)
20 min96 Rockwell B max (Annealed) 38-45 RC (Hardened)
416
S41600
Cutlery, dental & surgical instrumentsC 0.15 max, Mn 1.25 max, Si 1.0 max, Cr 12.0-14.0, P 0.06 max, S 0.15 min, Mo 0.60 max, Fe BalanceASTM A895 ASTM A194 AMMS 55610 SAE J4050.280
(7.74)
75-90
(517-621)
40-50
(276-345)
15-3038-45 Rc (Hardened)
AL 418 SPL
S41800
Engine braces, turbine exhaust components, exhaust struts, stiffeners, ductsC 0.15-0.20, Cr 12.0-14.0, Mn 0.50 max, Ni 1.8-2.2, P 0.04 max, S 0.03 max, Si 0.50 max, W 2.5-3.5, Fe BalanceAMS 55080.284
(7.87)
130
(900)
105
(725)
2025-50 Rockwell C (Hardened)
420
S42000
Cutlery, Dental and surgical instruments, nozzles, valve parts, hardened steel balls and seats for oil well pumps, separating screens and strainers, springs, shears, and wear surfacesC 0.15 min, Mn 1.0 max, Si 1.0 max, Cr 12.0-14.0, Ni 0.75 max, Mo 0.5 max S 0.03 max, P 0.04 max, Fe BalanceASTM A1760.280
(7.74)
85
(586)
45
(310)
2953-57 Rockwell C (Hardened)
440A
S44002
Cutlery, dental and surgical instruments, nozzles, valve parts, hardened steel balls and seats fro oil well pumps, separating screens and strainers, springs, shears, and wear surfacesC 0.60-0.75, Mn 1.0 max, Si 1.0 max, Cr 16.0-18.0, Mo 0.75 max, S 0.03 max, P 0.04 max, Fe BalanceASTM A2760.279
(7.72)
104
(717)
62
(427)
2057-60 Rockwell C (Hardened)
440C
S44004
Bearings, valve parts, cutlery and industrial knivesC 0.95-1.20, Mn 1.0 max, Si 1.0 max, Cr 16.0-18.0, Mo 0.75 max, S 0.03 max, P 0.04 max, Fe BalanceASTM A276 AMS 5630 QQ-S-7630.277
(7.68)
110
(760)
65
(450)
1558-61 Rockwell C (Hardened
Martensitic and Precipitation Hardening Steel Comparison Table
Martensitic Stainless Steel for Knife Applications – Part 1: Fe-Cr-C

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