METHOD FOR PRODUCTION OF CAST MULTILAYER WORKPIECE Russian patent published in 2020 - IPC B22D7/02 B32B15/01 C22F1/18 

FIELD: metallurgy.

SUBSTANCE: invention relates to production of cast multilayer billet of high alloyed steel. Core is made, the ingot is heated and cast, the concentric layer of metal is applied on the core, after which the workpiece is subjected to hot deformation. Core used is pre-melted and prepared rod, casting of multilayer workpiece is performed by casting metal into mould with pre-installed heated rod. Rod is preliminarily chemically cleaned by etching in a bath with an alkaline solution at the following ratio: NaOH 40÷45 %; NaNO₃ 30÷35 %; NaCl 10÷15 % and Na₂CO₃ is the rest, at temperature 400÷450 °C for 20÷30 minutes, then washed first in hot water at temperature of 70÷80 °C for 5÷7 minutes, then in cold water and dried in a drying chamber at temperature of 100÷110 °C.

EFFECT: broader technological capabilities.

1 cl, 1 dwg, 2 tbl