Heat Treat Diagram. Like any other martensitic stainless steel grade 420 can also be hardened by heat treatment to enhance mechanical properties. Cct diagrams which are directly related to the time temperature transformation ttt diagrams for the specific steel being treated.
For heat treatment of steels the first resource to become familiar with is the ironcementite equilibrium phase diagram which shows the equilibrium phases in ironcarbon alloys for a given temperature and composition. It is used to determine when transformations begin and end for an isothermal constant thermal heat treatment of a previously austenitized alloy. Such a ttt diagram for eutectoid steel is shown in figure 1.
Heat treatment diagrams are available for a huge number of materials in the total materia database.
If high carbon steel is quenched for hardening in a bath it becomes extra hard extra brittle and has unequal distribution internal stresses and strain and hence unequal harness and toughness in structure. West yorkshire steel are suppliers of 420 stainless steel grades in round bar plate and sheet. Heat treating powder metallurgy parts is a necessary process to control the properties of the final part such as hardness and strength. Its purpose is to provide an understanding of the heat treatment of iron and steels principally to those unacquainted with this subject.