The difference between carbon steel & Alloy steel

　　Tempering stability of alloy steel is better than carbon steel, which is due to alloying elements in steel tempering hindered the diffusion of atoms, and thus at the same temperature, martensite decomposition and delayed play against temper softening effect . Stability of tempering steel is more significant: the element vanadium, tungsten, titanium, chromium, molybdenum, cobalt, silicon and the like; of obvious are: aluminum, manganese, nickel and other elements. You can see, carbide-forming elements, the delay effect is particularly remarkable temper softening. Corporations are not the cobalt and silicon carbide forming elements, but they form and grow cementite nuclei, a strong retarding effect, therefore, there is delay temper softening effect. The extent of various alloying elements on the temper embrittlement effects are different. Qualitatively speaking, manganese, chromium, nitrogen, phosphorus, vanadium, copper, nickel, etc. have a tendency to temper brittleness. Molybdenum is special, it has joined the temper brittleness of steel (such as manganese, chromium, etc.), can significantly reduce the tendency to temper brittleness; if the individual joined ordinary carbon steel, become promote temper brittleness element tendencies. Tungsten and molybdenum similar effect, but the effect on the temper brittleness is not yet determined.