4140 peeled or turned steel round bar 4140 steel material is called in American and Australian standard such as aisi 4140, astm 4140, sae 4140, as 4140. It is one kind of Chromium-Molybdenum through-hardening steel of medium hardenability. It is a general purpose high-tensile steel with medium strength level and good impact properties. The equivalent materials are 42CrMo, SCM440, 42CrMo4 but there is little different in Mn content. The 4140 material Mn content is 0.75%-1.00%, other material Mn content is usually 0.60% - 0.90%. But this material is usually used after quenching and tempering, after the heat treatment, the mechanical properties can be same in these standard. As a factory, we can do cold drawing, peeling, centerless grinding and polished and also all kinds of heat treatment. So except the 4140 hot rolled alloy steel round bar, we can also supply 4140 cold drawn alloy steel round bar, 4140 peeled alloy steel round bar, 4140 groun…