4140 42CrMo4 SCM440 turned ground and polished steel bar 4140 shaft steel material is 4140 steel round bar after turned or peeled, cneterless ground and polishedsteel bar to be used as 4140 steel shafts in machinery or automobile parts. 4140 ground and polished steel bar is usually quenched and tempered to get higher mechanical properties and hardness. 4140 qt steel round bar is 4140 steel bar after quenching and tempering with oli quenching media before using, it can also be called as 4140 hardened steel bar or 4140 quenched & tempered steel bars, 4140 qt steel bar and 4140 ht steel bar. 4140 oqt steel bar has high hardness and good mechanical properties. We can produce 4140 ht steel rod with difference hardness mechanical properties according to customers different technical requirements. We can supply various 4140 oqt steel round bar such as 4140 tg&p steel bar, 4140 peeled & polished steel bar, 4140 cold drawn and QT steel bar etc. 4140…