PRODUCTION OF BIMETALLIC RODS Russian patent published in 2012 - IPC B23K20/04 

FIELD: process engineering.

SUBSTANCE: proposed method comprises fitting carbon steel core in steel shell to be heated and rolled in hot state in ''circle-circle'' pattern, first, in multipass gages and, then, in two-roll stands in ''oval-square'' pattern, and, finally, in multiroll gages in ''circle-circle'' pattern. Higher quality of weld joint between shell and core metals, uniform distribution of shell metal over core surface and ruled out anisotropy of strength of bimetal rods at bending stresses are ensured by decarbonising core surface to depth of 0.2-0.4 mm to content of carbon not exceeding 0.04% while shell diameters are selected to allow rustproof austenitic steel volume fraction before rolling of 20-30%. Roughing in multiroll gages in ''circle-circle'' pattern is carried out at temperature making 0.94-1.0 of metal Ac₃ temperature of the core decarbonised surface.

EFFECT: reduced labor and metal input.

1 tbl, 3 ex