Used for crankshafts, automobile axle beams, connecting rods and lightly stressed gears, and generally for moderately stressed parts of motor vehicles and general engineering.
EN-8 Medium carbon steel
Crankshafts, axle beams, connecting rods and lightly stressed gears in motor vehicles and general engineering.
Typical analysis, %
| C % | Si % | Mn % | P % | S % |
|---|
| 0.35-0.45 | 0.10-0.35 | 0.60-0.90 | 0.045 max | 0.045 max |
Heat treatment and processing
| Forging °C | Annealing / normalising °C | Hardening °C | Quench | Tempering °C | Hardness |
|---|
| 1050-1100 | 800-900 | 1000 | Oil, rapid cooling | 700-750 | BHN 159-229 |
Equivalent grades
| BS 970 (1970-72) | BS 970-1955 | AISI/SAE |
|---|
| 080M40 | En 8 | 1040 |
EN-9 Medium carbon steel
Crankshafts, cylinders, gears and sprockets; machine parts needing moderate wear resistance.
Typical analysis, %
| C % | Si % | Mn % | P % | S % |
|---|
| 0.50-0.60 | 0.10-0.35 | 0.50-0.80 | 0.045 max | 0.045 max |
Heat treatment and processing
| Forging °C | Annealing / normalising °C | Hardening °C | Quench | Tempering °C | Hardness |
|---|
| 1000-800 | 750-780 | 760-820 | Water | 150-200 | 59-62 HRC |
Equivalent grades
| BS 970 (1970-72) | BS 970-1955 | AISI/SAE | DIN |
|---|
| 070M55 | En 9 | 1055 | Ck55 |
EN-19 / SAE 4140 Chromium-molybdenum steel
Axle shafts, crankshafts, gears, connecting rods, studs, bolts and propeller shaft joints; heat-treated parts needing high tensile and impact strength with high bending endurance.
Typical analysis, %
| C % | Si % | Mn % | Cr % | Mo % | P % | S % |
|---|
| 0.35-0.45 | 0.10-0.35 | 0.50-0.80 | 0.90-1.20 | 0.20-0.40 | 0.05 max | 0.05 max |
Heat treatment and processing
| Forging °C | Annealing / normalising °C | Hardening °C | Quench | Tempering °C | Hardness |
|---|
| 1050-850 | 650-700 | 820-850 | Oil or water | 530-670 | BHN 201-277 |
Equivalent grades
| BS 970 (1970-72) | BS 970-1955 | AISI/SAE |
|---|
| 709M40 | En 19 | 4140 |
EN-24 / SAE 4340 Nickel-chromium-molybdenum steel
Aircraft and heavy vehicle crankshafts, connecting rods, gear shafts, camshafts, spindles, studs, pinions and boring bars; heat-treated components with large sections and exacting requirements.
Typical analysis, %
| C % | Si % | Mn % | Cr % | Mo % | Ni % | P % | S % |
|---|
| 0.36-0.44 | 0.10-0.40 | 0.45-0.70 | 1.0-1.40 | 0.20-0.35 | 1.30-1.70 | 0.040 max | 0.035 max |
Heat treatment and processing
| Forging °C | Annealing / normalising °C | Hardening °C | Quench | Tempering °C | Hardness |
|---|
| 1050-850 | 650-700 | 820-840 | Oil or water | 530-670 | BHN 201-277 |
Equivalent grades
| BS 970 (1970-72) | BS 970-1955 | AISI/SAE | DIN |
|---|
| 817M40 | En 24 | 4340 | 34CrNiMo6 |
EN-31 High carbon chromium steel
Ball and roller bearings, spinning tools, beading rolls, punches and dies; components facing severe abrasion, wear or high surface loading.
Typical analysis, %
| C % | Si % | Mn % | Cr % | P % | S % |
|---|
| 0.90-1.20 | 0.10-0.35 | 0.30-0.75 | 1.0-1.60 | 0.05 max | 0.05 max |
Equivalent grades
| BS 970 (1970-72) | BS 970-1955 | AISI/SAE | DIN |
|---|
| 534A99 | En 31 | 52100 | 100Cr6 |
EN-41B Nitriding steel
Nitriding steel supplied hardened and tempered to your specification, in round bars.
Typical analysis, %
| Si % | Mn % | Cr % | Al % | P % | S % |
|---|
| 0.10-0.45 | 0.65 max | 1.40-1.80 | 0.90-1.30 | 0.05 max | 0.055 max |
Equivalent grades
| BS 970 (1970-72) | BS 970-1955 | DIN |
|---|
| 905M31 | En 41B | 34CrAlMo6 |
Values are typical. Request the mill test certificate with your order.
