Patent ID: 6692593
Filing Date: 2004-02-17
Classification: C21D

Abstract:
A method for quenching metallic workpieces in a furnace space, comprising:subjecting a metallic workpiece to a heat treatment process in an evacuated furnace space; supplying an amount of hydrogen to the evacuated furnace space before a quenching gas or a quenching gas mixture is passed into the furnace space; and subsequently passing the quenching gas or quenching gas mixture comprising an inert gas or a mixture of inert gases into the furnace space, thereby quenching the metallic workpiece, wherein the amount of hydrogen supplied is limited so that, depending on a quenching pressure, a gas temperature at the end of the quenching, and a composition of the quenching gas or the quenching gas mixture, a hydrogen concentration below the explosive limit is obtained in the quenching gas or quenching gas mixture.