Alloy Structural Steel 25CrMo4 1.7218 AISI 4130 QT Forged Round Steel Bar

1: 4130 Steel Introduction
AISI 4130 alloy steel is a medium carbon, low alloy steel in ASTM A29 standard. ASTM 4140 steel is also commonly referred to as a chromoly steel, or chrome moly steel, containing nominally 0.28-0.33% Carbon, 0.8-1.1% Chromium and 0.15-0.25% Molybdenum. It is similar to 4140 steel which has a higher carbon level (0.28-0.33%), giving 4130 material improved weldability, at the expense of through thickness strength. With the proper heat treatment it is also readily machined. Annealing ASTM 4130 alloy steel offers excellent ductility. AISI 4130 steel is usually supplied as round bar commonly in the hardened and tempered condition.
2: 4130 Steel Equivalent
| Country | British | USA | Japan | BS |
| Standard | BS 970 | ASTM A29 | JIS G4105 | EN10083 |
| Grade | 708A25/708M25 | 4130 | SCM430 | 25CrMo4/1.7218 |
3: 4130 Steel Chemical Composition
| Grade | C | Si | Mn | P | S | Cr | Mo |
| 4130 | 0.28-0.33 | 0.15-0.35 | 0.4-0.6 | 0.035 | 0.04 | 0.8-1.1 | 0.15-0.25 |
| 25CrMo4 | 0.22-0.29 | 0.4 | 0.6-0.9 | 0.025 | 0.035 | 0.9-1.2 | 0.15-0.30 |
| SCM430 | 0.28-0.33 | 0.15-0.35 | 0.6-0.85 | 0.03 | 0.03 | 0.9-1.2 | 0.15-0.30 |
4: 4130 Steel Mechanical Properties
The mechanical properties mainly include tensile strength, yield strength, elongation, area or reduction, hardness, impact value, non-metalic inclusion etc. Different heat treatment, the mechanical properties will be different, such as normalized, tempered, QT. If you want to know the properties, kindly contact the salesman.
5: 4130 Steel Overviews
| Size | Round | Dia 6-1200mm |
| Plate/Flat/Block | Thickness 6mm-500mm | |
| Width 20mm-1000mm | ||
| Heat treatment | Normalized ; Annealed ; Quenched ; Tempered | |
| Surface condition | Black; Peeled; Polished; Machined; Grinded; Turned; Milled | |
| Delivery condition | Forged; Hot rolled; Cold drawn | |
| Test | Tensile strength, Yield strength, elongation, area of reduction, impact value, hardness, grain size, ultrasonic test, US inspection, magnetic particle testing, etc. | |
| Payment terms | T/T;L/C;/Money gram/ Paypal | |
| Trade terms | FOB; CIF; C&F; etc.. | |
| Delivery time | 30-45 days | |
| Application | 4130 are used for Commercial aircraft, aircraft engine mounts, automotive, machine tools, hydraulic tools, auto racing, aerospace, oil and gas industries as forged valve bodies and pumps, agricultural and defense industries etc. | |
6: Delivery Condition
For hot forged bar, usually the delivery condition is hot forged, annealed/QT rough turned/Black surface.
For hot rolled bar, usually the delivery condition is hot rolled, annealed/QT, Black surface.
For hot forged plate, usually the delivery condition is hot forged, annealed/QT, milled surface.
For hot rolled plate, usually the delivery condition is hot rolled, annealed/QT, black surface.
7. Alloy Round Bar Tolerance
| Diameter(mm) | Tolerance | ||
| Forged Steel Round Bar | 80-600 | Black Surface:0~+5 | Rough Machined or Turned:0~+3 |
| 650-1200 | Black Surface:0~+15 | Rough Machined or Turned:0~+3 | |
| Hot Rolled Steel Round Bar | 16-310 | Black Surface:0~+1 | Peeled:H11 |
| Cold Drawn Steel Round Bar | 6-100 | Black Surface:H11 | Peeled:H11 |



has the capacity to forge round steel, steel flat, square steel, module, shaft and roller, etc. The main specifications of the products include Φ80-1000mm forging materials and 80-1200mm square billets and which the maximum piece weight can reach 50T.
Company Main Products:(If you do not find the product you need, please contact us)
Cold Work Tool Steel | DIN 1.2080,DIN 1.2379,DIN 1.2436,DIN 1.2210,JIS SKS3,AISI O2 |
Hot Work Tool Steel | H13,DIN 1.2714,DIN 1.2767,DIN 1.2344(H13),DIN 1.2713 |
Engineering Steel | AISI 1020,AISI 1045,AISI1050,AISI 5140,AISI 4130,AISI 4140(40CrMo4),AISI 4340, DIN 1.5919,AISI 8620,S235JR,S355JR |
Plastic Mould Steel | P20,P20+S,P20+Ni,DIN 1.2083,DIN 1.2316,DIN 1.2085 |
Spring Steel | AISI 9260,AISI 5160,AISI 6150,65MN,55CrMnA |
Stainless Steel | 316L,201,301,304,316,410,420,430,431,440C,SUS630(DIN1.4542) |
High Speed Steel | DIN 1.3343(M2),DIN 1.3243(M35),DIN 1.3247,DIN 1.3265 |

We are professional manufacturer for many years. we can provide a wide range of steel products.
Usually bundling for large diameter,small diameter bars in bulk or as customer's demand.
The hardness after heat treatment is higher than D2/1.2379/Cr12Mo1V1, and can reach 61-63HRC after high-temperature tempering (525 ± 5 ℃); In terms of strength and wear resistance, it exceeds Cr12Mo1V1, and its toughness is higher than D2/1.2379/Cr12Mo1V1; The manufactured molds rarely have cracks and fissures, greatly improving their service life; The residual stress after wire cutting processing is smaller than that of Cr12Mo1V1; The cutting and grinding performance exceeds Cr12Mo1V1.
Suitable for manufacturing precision punching dies and stamping dies for cold forging, deep drawing, and wire rolling for wire cutting processing.