| 709M40 AS ROLLED / ANNEALED / HT (En 19) |
| BS 970 | SAE (AISI) | WERKSTOFF No |
| 709M40 | 4140 | 1.7225 |
| CHEMICAL COMPOSITION |
| Carbon | Silicon | Manganese | Chromium | Molybdenum | Sulphur | Phosphorus |
| 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. |
| MECHANICAL PROPERTIES |
| PROPERTY | HARDENED and TEMPERED CONDITION |
| R | S | T | U | V | |
| Limited Ruling Section Min. | 254 | 152 | 102 | 64 | 29 |
| Tensile Strength, MPa. Min. | 690 / 850 | 770 / 930 | 850 / 1000 | 64 | 29 |
| Yield Stress, MPa, Min. | 480 | 570 | 665 | 740 | 835 |
| Elongation percent, Min. | 15 | 15 | 13 | 12 | 12 |
| Izod Impact Value, Joule, Min. | 34 | 54 | 54 | 47.5 | 47.5 |
| Brinell Hardness Number | 201 / 255 | 223 / 277 | 248 / 302 | 269 / 321 | 293 / 341 |
| STANDARD STOCK SIZES IN THE "AS ROLLED" and HEAT TREATED CONDITION |
| SIZE | Kg/m | SIZE | Kg/m | SIZE | Kg/m | SIZE | Kg/m | SIZE | Kg/m | SIZE | Kg/m | |||||
| 20mm | 2.466 | 55mm | 18.650 | 90mm | 49.939 | 140mm | 120.841 | 210mm | 271.893 | 310mm | 591.976 | |||||
| 25mm | 3.853 | 60mm | 22.195 | 95mm | 55.642 | 150mm | 138.721 | 220mm | 298.403 | 350mm | 754.600 | |||||
| 30mm | 5.549 | 65mm | 26.049 | 100mm | 61.654 | 160mm | 157.833 | 230mm | 326.148 | 405mm | 1010.394 | |||||
| 35mm | 7.553 | 70mm | 30.210 | 108mm | 71.846 | 170mm | 178.179 | 240mm | 354.816 | xxx | xxxx | |||||
| 40mm | 9.865 | 75mm | 34.680 | 115mm | 81.537 | 180mm | 199.757 | 250mm | 385.336 | xxx | xxx | |||||
| 45mm | 12.485 | 80mm | 39.458 | 120mm | 88.781 | 190mm | 222.570 | 290mm | 518.056 | xxxx | xxx | |||||
| 50mm | 15.413 | 85mm | 44.545 | 130mm | 104.195 | 200mm | 246.614 | 305mm | 573.034 | xxx | xxx |
| TYPICAL USES |
|
Axle shafts, crankshafts, connecting rods, gears, high tensile bolts and studs, propeller shaft joints, rifle barrels and breech mechanisms for small arms parts, induction hardened trackpins. |