440, 440A, 440B, 440C, X90CrMoV18 high carbon martensitic stainless steel


440A, UNS S44002, X90CrMoV18, 1.4112, X105CrMo17, 1.4125, X70CrMo15, 1.4109, AISI 440B, AISI 440C High-carbon martensitic stainless steel accord to AMS 5631, AMS-QQ-S763, ASTM A276, ASTM F899, QQ-S-763, GE S-400, S-1000, EN 10088-1, ISO 683-17

440, 440A, 440B, 440C, X90CrMoV18 high carbon martensitic stainless steel - Introduction and Application

440A, UNS S44002, X90CrMoV18, 1.4112, X105CrMo17, 1.4125, X70CrMo15, 1.4109, AISI 440B, AISI 440C High-carbon martensitic stainless steel, can be heat treated to extremely high hardnesses, that possesses good strength, moderate corrosion resistance, and excellent hardness and wear resistance, characterized by high hardness >55 HRC, while maintaining good resistance to corrosive environments and resistance to operating temperatures <400 ℃,Stainless steel grade 440A can be easily machined in the annealed condition. Carbide or ceramic tooling is recommended for performing machining. Chip breakers enable easy handling of tough stringy chips. As this steel has the tendency to air harden, welding is not performed; however if it is required, the steel should be preheated to 260°C (500°F) and post-weld treated at 732-760°C (1350-1400°F) for 6 h. This is followed by a slow furnace cooling to avoid cracking. 440A stainless steel is annealed at 843-871°C (1550-1600°F), followed by very slow furnace cooling. For performing hot working, the materials needs to be preheated to 760°C (1400°F) and then slowly increased to 1038-1204°C (1900-2200°F) before proceeding. The material should then be cooled slowly after working and once again cooled at room temperature. Finally it must be annealed fully. This material should not be heated below 927°C (1700°F). For performing tempering, grade 440A should be soaked at 148°C (300°F). Similarly for hardening, the material should be heated slowly to 760°C (1400°F), then soaked at 1010°C (1850°F), finally air or oil cooled.it has slightly less carbon than 440B and 440C giving it better machinability but less hardness, good wear resistance and high hardness makes this alloy an excellent candidate for cutting tools and knife blades, Cutlery, Bearings, Gage blocks, Molds and dies, Valve components, Turbine components, Medical instruments, Aircraft structural parts, Knives and measuring instruments.  It also is often used for dental and surgical equipment accord to AMS 5631, AMS 5632, ASTM A276, ASTM A314, ASTM A473, ASTM A511, ASTM A580, SAE 51440A,  MIL-S-862, SAE J405 (51440A), AMS-QQ-S763, ASTM A276, ASTM F899, QQ-S-763, GE S-400, S-1000, EN 10088-1, ISO 683-17.

High-carbon stainless steel is characterized by a special martensitic structure. It was from her are manufactured components, which are then subject to high temperature hardening and tempering. Is characterized by a very high abrasion resistance and hardness. Not subject to weld. Needs polishing before its various technological processes. Hardening occurs at temperatures between 1000-1050 °C. The process of tempering at temperatures from 100-300 °C. This is due to the extreme hardness is a very distinctive species. The reason is the high content of carbon in the steel composition, which, however, makes the steel is sufficiently resistant to corrosion and high temperatures (above 400 °C). In terms of the characteristics of the steel grade can be classified as a stainless-steel lock or tool.

Steel with this species is used in the food industry for the production of various types of cutting tools, machinery and other equipment. It is used to manufacture surgical blades, liners, castings, elements used in the processing of plastics for the production of knives; in the construction industry to build tools, grips workpieces whether clamping in the construction of machines and vehicles. A medium level of machinability and poor corrosion resistance. In addition, the grade of stainless steel is used for the production of valves, bushings, rolling bearings. Steel is also used for the hardened valve seat and used in the chemical industry. It is used for the production of sleeves, rings, shafts, ball bearings, hunting knives. Due to the carbon content, this steel has some limitations in combination with aggressive work environments.

Stainless steel X105CrMo17 is characterized by hardness of 55-57 HRC, and the modulus of elasticity E 215 GPa. The best conditions for the heat treatment of plastic and steel: forging and rolling in temperature from 1100-800 °C, annealing-780-840 °C. The steel is very resistant to cold solutions of salt, some organic and inorganic dilute acids, gasoline, liquid fuel, oil vapors, hot, hot, hot, oxides of dilute nitric acid, alcohols and food products in which configurations are preservatives. By comparing, steel X90CrMoV18 is a much better grade than 4H13 due to the larger blade hardness, which less and are bent over and much higher corrosion resistance.



Melted process

AOD


440, 440A, 440B, 440C, X90CrMoV18 high carbon martensitic stainless steel - Chemical composition WT %

GradeChemical Composition WT %
CMnSiPSCrNiMoVCuCo
X105CrMo17, 1.41250.95 - 1.20Max 1.0Max 1.0Max 0.04Max 0.0316.0 - 18.0-0.4 - 0.8---
X90CrMoV18, 1.41120.85 - 0.95Max 1.0Max 1.0Max 0.04Max 0.0317.0 - 19.0-0.9 - 1.30.07 - 0.12--
X108CrMo17, 1.35430.95 - 1.20Max 1.0Max 1.0Max 0.04Max 0.0316.0 - 18.0-0.4 - 0.8---
X105CrCoMo18-2, 1.45281.00 - 1.10Max 1.0Max 1.0Max 0.045Max 0.0316.5 - 18.5-1.0 - 1.50.07 - 0.12-1.3 - 1.8
95Ch18, 95Kh18, 95Х180.9 - 1.0Max 0.8Max 0.8Max 0.03Max 0.02517.0 - 19.0Max 0.6Max 0.2Max 0.2--
X70CrMo15, 1.41090.60 - 0.75Max 1.0Max 0.7Max 0.04Max 0.0314.0 - 16.0-0.4 - 0.8---
440A, UNS S440020.60 - 0.75Max 1.0Max 1.0Max 0.04Max 0.0316.0 - 18.0-Max 0.75


440B, UNS S440030.75 - 0.95Max 1.0Max 1.0Max 0.04Max 0.0316.0 - 18.0-Max 0.75---
440C, UNS S440040.95 - 1.20Max 1.0Max 1.0Max 0.04Max 0.0316.0 - 18.0-Max 0.75---
440F, UNS S440200.95 - 1.20Max 1.25Max 1.0Max 0.06Max 0.1516.0 - 18.0Max 0.5--Max 0.6-

Mechanical Property of 440, 440A, 440B, 440C, X90CrMoV18 high carbon martensitic stainless steel

PropertiesMetricImperial
Tensile strength725-1790 MPa105000 - 260000 psi
Yield strength (@strain 0.200 %)415-1650 MPa60200 - 239000 psi
Modulus of elasticity204 - 215 GPa29600 - 31200 ksi
Elongation at break (in 50 mm)5- 20%5- 20%
Hardness, Rockwell B9595
  • Thermal conductivity, λ20℃: 15 W * m-1 * K-1
  • Linear expansion coefficient, α = 10,4 * 10-6 * K-1
  • Heat capacity, cp = 430 J * kg-1 * K-1
  • Resistance: 0,8 mkOhm * m
  • Modulus of elasticity, E = 215 GPa
  • Density = 7,7 g/cm3
  • Hardness in annealed condition +1C, +1E, +1D, +1X, +1G, +2D: < 285HB
  • Hardness after hardening and tempering of steel 1.4112 / X90CrMoV18: 55-57 HRC
  • Hardness after hardening and tempering steel 1.4125 / X105CrMo17: 57-60 HRC

Mechanical properties of X90CrMoV18, 1.4112
  • softening annealing at a temperature of 780 - 840℃ with cooling in air or furnace
  • Hardening at 1000 - 1080 ℃ with cooling in water or oil
  • Tempering at a tempering of 100 - 200℃
Mechanical properties of X105CrMo17, 1.4125
  • softening annealing at a temperature of 780 - 840℃ with cooling in air or furnace
  • Hardening at 1000 - 1050℃ with cooling in oil
  • Tempering at a tempering of 100 - 300℃
Mechanical properties of H18 steel
  • softening annealing at a temperature of 850 - 900℃ with cooling in furnace
  • Hardening at 1000 - 1050℃ with cooling in oil
  • Tempering at a tempering of 200 - 300℃

Heat Resistance

440 stainless steels should not be used at temperatures below the relevant tempering temperature, due to loss of mechanical properties caused by over-tempering.


Physical Property of 440, 440A, 440B, 440C, X90CrMoV18 high carbon martensitic stainless steel

  • Physical Properties for X90CrMoV18, 1.4112
    • softening annealing at a temperature of 780 - 840℃ with cooling in air or furnace
    • Hardening at 1000 - 1080 ℃ with cooling in water or oil
    • Tempering at a tempering of 100 - 200℃
  • Physical Properties for X105CrMo17, 1.4125
    • softening annealing at a temperature of 780 - 840℃ with cooling in air or furnace
    • Hardening at 1000 - 1050℃ with cooling in oil
    • Tempering at a tempering of 100 - 300℃
  • Physical Properties for H18 steel
    • softening annealing at a temperature of 850 - 900℃ with cooling in furnace
    • Hardening at 1000 - 1050℃ with cooling in oil
    • Tempering at a tempering of 200 - 300℃

Heat Treatment of 440, 440A, 440B, 440C, X90CrMoV18 high carbon martensitic stainless steel

Annealing — 440 stainless steels are full annealed at 850 to 900°C, followed by slow furnace-cooling at about 600°C and air-cooling. Sub-critical annealing is carried out at 735 to 785°C, followed by slow furnace-cooling.

Hardening — 440 stainless steels are heated at 1010 to 1065°C, then quenched in air or oil. Oil quenching is usually carried out for heavy sections. Following this process, these steels are tempered at temperatures from 150 to 370°C, to achieve a high hardness and improved mechanical properties.

Tempering at temperatures between 425 and 565°C should be avoided as the corrosion and impact resistance properties of grade 440 tend to reduce in this range. Also, tempering of these grades at 590 to 675°C will result in high impact resistance and loss of hardness.

  • Heat treatment for X90CrMoV18, 1.4112
    • softening annealing at a temperature of 780 - 840℃ with cooling in air or furnace
    • Hardening at 1000 - 1080 ℃ with cooling in water or oil
    • Tempering at a tempering of 100 - 200℃
  • Heat treatment for X105CrMo17, 1.4125
    • softening annealing at a temperature of 780 - 840℃ with cooling in air or furnace
    • Hardening at 1000 - 1050℃ with cooling in oil
    • Tempering at a tempering of 100 - 300℃

Welding of 440, 440A, 440B, 440C, X90CrMoV18 high carbon martensitic stainless steel

During welding 440 stainless steels are pre-heated at 250°C, followed by full annealing. Grade 420 filler rods can be used to achieve a high hardness weld. Grade 309 or 310 filler rods will, however, provide soft welds, having high ductility.


Machining of 440, 440A, 440B, 440C, X90CrMoV18 high carbon martensitic stainless steel

440 stainless steels can be easily machined in their annealed state. Machining these grades after hardening is extremely difficult, or impossible in some cases.


Equivalent grades of 440, 440A, 440B, 440C, X90CrMoV18 high carbon martensitic stainless steel

GradeUNS NoOld BritishEuronormSwedish SSJapanese JIS
BSEnNoName
440AS44002  -- SUS 440A
440BS44003  1.4112X90CrMoV18 SUS 440B
440CS44004--1.4125X105CrMo17-SUS 440C

440, 440A, 440C, SUS 440C, SUS 440B, CSN 17042, 9Ch18, X10CrMo17, 90Cr180, X105CrMo17, 1.4125, X90CrMoV18, 1.4112, X 105 CrMo 17, X 90 CrMoV 18, 1.4528, X105CrCoMo18-2, 1.4109, X70CrMo15, AISI 440A, AISI 440C, AISI 440B, AISI 440F, 9Cr18MoV, 11Cr17, 110CrMo17, X36CrMo17, X91CrMoV18, 90VMoCr180, UNS S44003, UNS S44004, UNS S44020, UNS S44025, 14-4CrMo, 1.3543, X108CrMo17, 110Х18М, 95Х18, 110Ch18M, 95Ch18, Z100CD17CI, Z 100 CD 17 CI


440, 440A, 440B, 440C, X90CrMoV18 high carbon martensitic stainless steel Martensitic & Precipitation hardened stainless steel stock list

Grade Shape Dimensionmm Qty.kg
X90CrMoV18 Round bar 30mm 1632
X90CrMoV18 Round bar 35mm 1239
X90CrMoV18 Round bar 40mm 2698
X90CrMoV18 Round bar 50mm 3156
X90CrMoV18 Round bar 60mm 6985
X90CrMoV18 Round bar 80mm 4698
X90CrMoV18 Round bar 100mm 3987
X90CrMoV18 ESR Ingot 59850