AISI 4130 Alloy Steel (UNS G41300)

Topics Covered

Introduction
Chemical Composition
Physical Properties
Mechanical Properties
Thermal Properties
Other Designations
Fabrication and Heat Treatment
     Machinability
     Forming
     Welding
     Heat Treatment
     Forging
     Hot Working
     Cold Working
     Annealing
     Tempering
     Hardening
Applications

Introduction

Alloy steels are designated by AISI four-digit numbers. They are more responsive to mechanical and heat treatments than carbon steels. They comprise different types of steels with compositions which exceed the limitations of B, C, Mn, Mo, Ni, Si, Cr, and Va in the carbon steels. 

AISI 4130 alloy steel contains chromium and molybdenum as strengthening agents. It has low carbon content, and hence it can be welded easily. The datasheet given below provides more details about AISI 4130 alloy steel. 

Chemical Composition

The chemical composition of AISI 4130 alloy steel is listed in the following table.

Element Content (%)
Iron, Fe 97.03  98.22
Chromium, Cr 0.80  1.10
Manganese, Mn 0.40  0.60
Carbon, C 0.280  0.330
Silicon, Si 0.15  0.30
Molybdenum, Mo 0.15  0.25
Sulfur, S  0.040
Phosphorous, P  0.035

Physical Properties

The following table shows the physical properties of AISI 4130 alloy steel.

Properties Metric Imperial
Density 7.85 g/cm3 0.284 lb/in³
Melting point 1432°C 2610°F

Mechanical Properties

The mechanical properties of AISI 4130 alloy steel are outlined in the following table.

Properties Metric Imperial
Tensile strength, ultimate 560 MPa 81200 psi
Tensile strength, yield 460 MPa 66700 psi
Modulus of elasticity 190-210 GPa 27557-30458 ksi
Bulk modulus (Typical for steel) 140 GPa 20300 ksi
Shear modulus (Typical for steel) 80 GPa 11600 ksi
Poissons ratio 0.27-0.30 0.27-0.30
Elongation at break (in 50 mm) 21.50% 21.50%
Reduction of area 59.6 59.60%
Hardness, Brinell 217 217
Hardness, Knoop (Converted from Brinell hardness) 240 240
Hardness, Rockwell B (Converted from Brinell hardness) 95 95
Hardness, Rockwell C (Converted from Brinell hardness, value below normal HRC range, for comparison purposes only.) 17 17
Hardness, Vickers (Converted from Brinell hardness) 228 228
Machinability (Annealed and cold drawn. Based on 100% machinability for AISI 1212 steel.) 70 70

Thermal Properties

The thermal properties of AISI 4130 alloy steel are outlined in the following table.

Properties Metric Imperial
Thermal conductivity (100°C) 42.7 W/mK 296 BTU in/hr.ft2. °F

Other Designations

Other designations that are equivalent to AISI 4130 alloy steel include the following.

AMS 6348 AMS 6371 ASTM A331 ASTM A829 DIN 1.7218
AMS 6350 AMS 6373 ASTM A506 MIL S-18729 UNI 25 CrMo 4
AMS 6351 AMS 6374 ASTM A507 MIL S-6758 JIS SCCrM 1
AMS 6360 AMS 6528 ASTM A513 SAE J1397 JIS SCM 2
AMS 6361 AMS 7496 ASTM A519 SAE J404 SS 2225
AMS 6362 ASTM A29 ASTM A646 SAE J412 B.S. CDS 110
AMS 6370 ASTM A322 ASTM A752 AFNOR 25 CD 4 (S) SAE J770

Fabrication and Heat Treatment

Machinability

AISI 4130 steel can be easily machined using conventional methods. However, machining becomes difficult when the hardness of the steel is increased.

Forming

Forming of AISI 4130 steel can be performed in the annealed condition.

Welding

Welding of AISI 4130 steel can be performed by all commercial methods.

Heat Treatment

AISI 4130 steel is heated at 871°C (1600°F) and then quenched in oil. This steel is usually heat-treated at temperatures ranging from 899 to 927°C (1650 to 1700°F).

Forging

Forging of AISI 4130 steel can be performed can be performed at 954 to 1204°C (1750 to 2200°F).

Hot Working

Hot working of AISI 4130 steel can be done at 816 to 1093°C (1500 to 2000°F).

Cold Working

AISI 4130 steel can be cold worked using conventional methods.

Annealing

AISI 4130 steel can be annealed at 843°C (1550°F) followed by air cooling at 482°C (900°F).

Tempering

Tempering of AISI 4130 steel can be performed at 399 to 566°C (750 to 1050°F), depending on the desired strength level.

Hardening

Hardening of AISI 4130 steel can be done with cold working or heat treatment.

Applications

The following are some of the major applications of AISI 4130 alloy steel:

  • Aircraft engine mounts
  • Welded tubing
Date Added: Sep 6, 2012 | Updated: Nov 12, 2012
Tell Us What You Think

Do you have a review, update or anything you would like to add to this article?

Leave your feedback
Submit