AISI 4140/SCM440/42Crmo4 Hot Rolled Steel Bar , Alloy Steel Round
Bar ,Tool Steel Bar
Description:4140 is a 1% chromium - molybdenum medium hardenability general
purpose high tensile steel - generally supplied hardened and
tempered in the tensile range of 850 - 1000 Mpa (condition T).
4140 is now available with improved machinability, which greatly
increases feeds and/or speeds, while also extending tool life
without adversley affecting mechanical properties.
Pre hardened and tempered 4140 can be further surface hardened by
flame or induction hardening and by nitriding.
APPLICATIONS:
It is the most commonly used of the high tensile steels with a wide
range of applications in automotive, Gear and Engine construction,
Crankshafts, Steering knuckles, Connecting rods, Spindles,
Intermediate gears, Pump and Gear shafts, Axles, Nuts and Bolts,
bearing, gear, transmission gear, supercharger gear, engine
cylinder, spring, 1200mm-2000mm rotary shouldered connections for
petroleum industry, jar knocker.
Chemical Composition (%):
| C | Si | Mn | P(max) | S(max) | Cr | Mo |
| 0.38-0.45 | 0.17-0.37 | 0.50-0.80 | 0.04 | 0.04 | 0.90-1.20 | 0.15-0.25 |
Process: EAF+LF+VOD+Forged+Heat Treatment(optional)
SIZE RANGE:Dia:10-320mm
SURFACE FINISHES:
Black, Peeled(K12), Cold Drawn, Turned & Polished(H10, H11),
Precision Ground(H9, H8)
Test: Ultrasonic test according to SEP 1921-84 .
Machining
4140 in the hardened and tempered as supplied condition has good
machinability , operations such as sawing, turning, drilling,
broaching, hobbing, milling and tapping can be carried out
satisfactoraly using machine manufacturers recommendations for
suitable tool type - feeds and speeds.
