709M40 Alloy Steel

709M40 is a 1% Cr-Mo medium hardenability general purpose high tensile steel. It is generally supplied in the Hardened and Tempered condition in the tensile range of 850 – 1000Mpa (T Condition) but can be heat treated to 700 – 1200Mpa dependent on section size (R – W Condition). This alloy is used in most industry sectors for a wide variety of applications. Typical uses include Drive shafts, couplings, bolts and gears, together with many surface and sub-surface components in the oil and gas industries. This grade also has reasonably good impact properties at low temperatures and can be good for some elevated temperature uses. 709M40 can be further surface hardened by either flame or induction hardening methods, giving case hardnesses in excess of 50 HRc.