AISI 4140 Alloy Steel | 42CrMo4 | 42CrMoS4 | 1.7225 | SCM440 | 42CrMo
Ningbo Ningshing Precision Machinery Group Co., Ltd.is the leading stockist of AISI 4140 alloy steel. We have running stock of solid round bars dia.16-300mm, steel plate size of 14-150 x 2000-2300mm. Annealed or Prehardened condition. We can also do furthur machining as per customers' requirement.
AISI/SAE 4140 Alloy Steel is a versatile alloy with good atmospheric corrosion resistance and reasonable strength. It shows good overall combinations of strength, toughness, wear resistance and fatigue strength.
Hot Rolled Round: dia.16-300 mm
Forged Round: dia.150-1200 mm
Cold Drawn Round: dia.6-30 mm
Hot Rolled Plate: 10-150 x 2000-2300 mm
Forged Block: 150-1000 x 200-1900 mm
EAF+LF+VD, Hot Rolled or Forged or Cold Drawn, Annealed or Q+T, Black surface or Machined surface, UT SEP1921 Class3 C/c or D/d
|AISI / SAE ||DIN / W.Nr ||JIS||GB|
|4140||42CrMo4 / 42CrMoS4 / 1.7225 ||SCM440||42CrMo|
|Other designations equivalent to AISI 4140 alloy steel are listed in the following table.|
|AMS 6349 ||ASTM A193 (B7, B7M) ||ASTM A506 (4140) ||ASTM A752 (4140) |
|AMS 6381 ||ASTM A194 (7, 7M) ||ASTM A513 ||ASTM A829 |
|AMS 6382 ||ASTM A29 (4140) ||ASTM A513 (4140) ||SAE J1397 (4140) |
|AMS 6390 ||ASTM A320 (L7, L7M, L7D) ||ASTM A519 (4140) ||SAE J404 (4140) |
|AMS 6395 ||ASTM A322 (4140) ||ASTM A646 (4140) ||SAE J412 (4140) |
|AMS 6529 ||ASTM A331 (4140) ||ASTM A711 |
Chemical Composition (%)
|Steel Grade ||C||Si||Mn||P||S||Cr||Mo|
|42CrMo4||0.38-0.45||≤ 0.40 ||0.60-0.90||≤ 0.035 ||≤ 0.035 ||0.90-1.20||0.15-0.30|
|42CrMoS4||0.38-0.45||≤ 0.40 ||0.60-0.90||≤ 0.035 ||0.020-0.040||0.90-1.20||0.15-0.30|
|4140||0.38-0.43||0.15-0.35||0.75-1.00||≤ 0.035 ||≤ 0.040 ||0.80-1.10||0.15-0.25|
|SCM440||0.38-0.43||0.15-0.35||0.60-0.85||≤ 0.035 ||≤ 0.040 ||0.90-1.20||0.15-0.30|
|42CrMo||0.38-0.45||0.17-0.37||0.50-0.80||≤ 0.035 ||≤ 0.035 ||0.90-1.20||0.15-0.25|
AISI 4140 Alloy Steel is used for as wide variety of applications where greater toughness and wear resistance is needed over lower carbon grades. Typical applications for 4140 tool steel uses include Components, Adapters, Arbors,strippers, holder blocks, mold bases, ejectors, back up and support tooling, fixtures, jigs, molds, cams, drill collars, Axle Shafts, Bolts, Crankshafts,stubs, couplings, reamer bodies, axles, shafting, piston rods, rams, hydraulic machinery shafts, gears, sprockets, gear racks, chain links, spindles, tool bodies, tool holders, tie rods, Connection Rods, Chuck Bodies, Collets, Conveyor Pins & Rolls, Ejector Pins, Forks, Gears, Guide Rods, Hydraulic Shafts & Parts, Lathe Spindles, Logging Parts, Milling Spindles, Motor Shafts, Nuts, Pinch Bars, Pinions, Pump Shafts,boring bars,tracks, slides, wear strips or parts, forming dies, brake dies, trim dies, bolsters, machinery parts and components, etc.
|Tensile strength ||655 MPa ||95000 psi |
|Yield strength ||415 MPa ||60200 psi |
|Bulk modulus(typical for steel) ||140 GPa ||20300 ksi |
|Shear modulus (typical for steel) ||80 GPa ||11600 ksi |
|Elastic modulus ||190-210 GPa ||27557-30458 ksi |
|Poisson’s ratio ||0.27-0.30||0.27-0.30|
|Elongation at break (in 50 mm) ||25.70%||25.70%|
|Hardness, Brinell ||197||197|
|Hardness, Knoop (converted from Brinell hardness) ||219||219|
|Hardness, Rockwell B (converted from Brinell hardness) ||92||92|
|Hardness, Rockwell C (converted from Brinell hardness. Value below normal HRC range, for comparison purposes only) ||13||13|
|Hardness, Vickers (converted from Brinell hardness) ||207||207|
|Machinability (based on AISI 1212 as 100 machinability) ||65||65|
Fabrication & Heat Treatment
AISI 4140 alloy steel has good machinability in the annealed condition.
AISI 4140 alloy steel has high ductility. It can be formed using conventional techniques in the annealed condition. It requires more pressure or force for forming because it is tougher than plain carbon steels.
AISI 4140 alloy steel can be welded using all conventional techniques. However, the mechanical properties of this steel will be affected if it is welded in the heat treated condition, and post weld heat treatment should be performed.
AISI 4140 alloy steel is heated at 845°C (1550°F) followed by quenching in oil. Before hardening, it can be normalized by heating at 913°C (1675°F) for a long period of time followed by air cooling.
AISI 4140 alloy steel is forged at 926 to 1205°C (1700 to 2200°F)
AISI 4140 alloy steel can be hot worked at 816 to 1038°C (1500 to 1900°F)
AISI 4140 alloy steel can be cold worked using conventional methods in the annealed condition.
AISI 4140 alloy steel is annealed at 872°C (1600°F) followed by slowly cooling in the furnace.
AISI 4140 alloy steel can be tempered at 205 to 649°C (400 to 1200°F) depending upon the desired hardness level. The hardness of the steel can be increased if it has lower tempering temperature. For example, tensile strength of 225 ksi cab be achieved by tempering at 316°C (600°F), and a tensile strength of 130 ksi can be achieved by tempering at 538°C (1000°F).
AISI 4140 alloy steel can be hardened by cold working, or heating and quenching.