Effect of aging and plastic deformation on the thermal and mechanical properties of the 20N34K5F invar

Mechanical and thermal properties of the 20N34K5F invar subjected to variou s thermomechanical and heat treatments including plastic deformation and ca rbide-precipitation aging were studied. The mechanical properties attained are comparable with those of the N36K10T3 invar age-hardenable at the expen se of fine intermetallics. The thermal properties of the 20N34K5F and N36K1 0T3 invars are virtually the same. The N36K10T3 invar was shown to have a h igher strength after three strengthening treatments, but the 20N34K5F invar is characterized by more rapidly increasing yield strength and ultimate te nsile strength during cold plastic deformation.