AISI 4140 Q&T Steel Properties / AISI 4140 High Tensile Steel
4140 alloy steel material is a high quality Quenched and Tempered Alloy Structural steel, It belong to the high quality medium carbon alloy steel, Oil Quenched & Tempered Hardenss is 28-34 HRC.4140 Annealing delivery hardenss less than 250HB
1. AISI 4140 equivalent material
♦JAPAN♦ : JIS SCM440 alloy steel
♦GERMANY♦ : DIN WN-r 1.7255 / 42CrMo4 steel alloy
♦CHINA♦ : GB 42CrMo steel
♦BRITISH♦ : BS 708M40
2.Supply Size range
Hot Rolled 4140 steel bar: Ø16mm-310mm
Forging 4140 steel bar: Ø250mm-1000mm
Cold drawn 4140 steel bar:Ø12-100mm
Q&T 4140 steel bar:Ø16-310mm
3.AISI 4140 alloy steel Chemical composition
| ASTM A29/29M |
C |
Si |
Mn |
Cr |
Mo |
P |
S |
| 4140 |
0.38~0.43 |
0.15~0.35 |
0.75~1.00 |
0.80~1.10 |
0.15~0.25 |
≤0.035 |
≤0.040 |
| DIN WN-r |
C |
Si |
Mn |
Cr |
Mo |
P |
S |
| 1.7225 |
0.38~0.45 |
≤0.40 |
0.60~0.90 |
0.90~1.20 |
0.15~0.30 |
≤0.035 |
≤0.035 |
| GB/T |
C |
Si |
Mn |
Cr |
Mo |
P |
S |
| 42CrMo |
0.38~0.45 |
0.17~0.37 |
0.50~0.80 |
0.90~1.20 |
0.15~0.25 |
≤0.030 |
≤0.030 |
| BS |
C |
Si |
Mn |
Cr |
Mo |
P |
S |
| 708M40 |
0.36~0.44 |
0.10~0.35 |
0.70~1.00 |
0.90~1.20 |
0.15~0.25 |
≤0.035 |
≤0.035 |
| JIS |
C |
Si |
Mn |
Cr |
Mo |
P |
S |
| SCM440 |
0.38~0.43 |
0.15~0.35 |
0.60~0.85 |
0.90~1.20 |
0.15~0.30 |
≤0.030 |
≤0.030 |
4.4140 heat treatment
Annealing
AISI 4140 alloy steel is annealed at 872°C (1600°F) followed by slowly cooling in the furnace.
Tempering
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).
Hardening
AISI 4140 alloy steel can be hardened by cold working, or heating and quenching.
5.Payment terms: T/T or L/ C
(1)30% paid by T/T and rest 70% by T/T upon the copy of B/B.
(2)100% irrevocable L/C at sight
6.Delivery time:within 7 days after your deposit or L/C.
7.Trade term: FOB CFR CIF
8.Port of loading:Qingdao , China
9. Mark: including steel material, heat No., pieces, weight, date and so on.
10.Quality control
1.Process for Steel round bar
Blast Furnance→ Molten Iron Pretreatment→Converter→LF→VD/RH→ContinuousCasting→Hot Rolling(KOCKS)→ Heat Treatment→ UT Inspection→Finish Product
EAF→LF→VD/RH→ Continuous Casting→Hot Rolling(KOCKS)→ Heat Treatment→ UT Inspection→ Finish Product
2.Grain Sizes:5-8
3.Surface condition: The surface of the bar shall be free cracks, scar and wrinkles at affect the use of the billets.
4.The mill test certificate shall show the chemical composition, and it is guaranteed that the chemical composition
shall be within the limit stipulated in the contract
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