B5970 708M40
A versatile low alloy steel that possesses good tensile and shock resistance properties combined with ductility. Its resistance to wear can be considerably increased by flame hardening and it is also suitable for nitriding (for maximum wear and abrasion resistance). Bars are often supplied in the hardened and tempered condition with a tensile strength range of 850-1000N/mm2• The bars are readily machinable so that the components can be put into service without the cost of further treatment. Bars can also be supplied in the softened state which require hardening and tempering but will give increased machinability.
Perfect for axle shafts, crankshafts, gears, induction hardened pins
Material Condition: Untreated/ Annealed/ Quench and tempered
Surface Finish: As rolled/ As forged/ Bright drawn/ Bright turned
708M40 Steel Making
| C | Si | Mn | S | P | Cr | Ni* | Mo | |
| Min | 0.36 | 0.10 | 0.70 | 0.90 | 0.15 | |||
| Max | 0.44 | 0.35 | 1.00 | 0.040 | 0.035 | 1.20 | 0.40 | 0.25 |
(* Denotes residual element)
708M40 Typical Mechanical Properties
| Test Type | Tensile and hardness test (at room temperature} | Impact test (KV) | |||||||
| Yield (RE) | 0.2% Proof | UTS (Rm) | Elong (A) | R of A (Z) | Hardness | Room Temp | |||
| Unit | N/mm2 | N/mm2 | N/mm2 | % | % | HB | J | ||
| Annealed | Min | ||||||||
| Max | 235 | ||||||||
| Q + T + Drawn, condition 'T' | Min | 700 | 850 | 9 | 248 | 50 | |||
| Max | 1000 | 302 | |||||||
| Q + T to condition 'Q' | Min | 480 | 625 | 18 | 179 | 16 | |||
| Max | 775 | 229 | |||||||
| Q + T to condition 'R' | Min | 495 | 700 | 15 | 201 | 28 | |||
| Max | 850 | 255 | |||||||
| Q + T to condition 'S' | Min | 585 | 775 | 15 | 223 | 50 | |||
| Max | 925 | 277 | |||||||
| Q + T to condition 'T' | Min | 680 | 850 | 13 | 248 | 50 | |||
| Max | 1000 | 302 | |||||||
