40CR4B STEEL
Introduction to 40CR4B STEEL GRADE
40Cr4B steel bars are a specialized grade of heat-treatable alloy steel, known for their excellent strength and durability in demanding applications. This chromium-manganese steel offers enhanced hardenability, making it suitable for forging and bright bar forms. Commonly used in the automotive and engineering sectors, 40Cr4B provides a balance of toughness and wear resistance after quenching and tempering.
40Cr4B steel is a heat treatable steel for driving elements as crankshafts, front vehicle axles, axle journals, steering components.
We can give you 40Cr4B regularly from sizes 23.5mm to 65mm.
We are supplier of 40Cr4B steels to a number of companies in Mumbai, Pune (eg Chakan, Bhosari, Ranjangaon, etc), Aurangabad, Ahmednagar, Rajkot, Thane, Nagpur, etc. All our 40Cr4B supplied is Ultrasound and MPI inspected.
Chemical composition % of grade 40Cr4B steel
| C | Si | Mn |
0.35 – 0.40 | max 0.35 | 0.6 – 0.9 |
| P | S | Cr |
max 0.035 | 0.015 – 0.035 | 1.0 – 1.2 |
For your requirements kindly call us today on 9004064570 or email us on sales@ambhe.com
Equivalent Grades to 40Cr4B Steel
40Cr4B is comparable to international standards:
- DIN: 41Cr4 or 1.7035
- SAE/AISI: 5140
- JIS: SCr440
- GB: 40Cr (with boron variant)
These equivalents ensure global sourcing compatibility.
FAQs
Q1. Is 40Cr4B the same as 41Cr4 / AISI 5140?
They are closely corresponding chromium steels used for quench-and-temper applications; 41Cr4 (1.7035) / AISI 5140 datasheets are commonly referenced for chemistry and properties. Always check melt-specific TCs.
Q2. What tolerances can I get on bright bars?
For bright rounds, h9–h11 per ISO 286-2 / EN 10278 are typical; centreless-ground bars can achieve h7.
Q3. What heat treatment is typical?
Q&T to achieve ~800–950 MPa tensile with balanced toughness for medium sections; induction surface hardening is common for wear zones.
Q4. Can I weld 40Cr4B?
Yes, with preheat and controlled heat input, followed by slow cooling/stress relief to minimise cracking risks
Q5. What applications are typical in India?
Automotive/tractor axles, shafts, knuckles, gear hubs, pump/valve parts—anywhere you need surface hardness with a tough core.