Patent ID: 9321103
Filing Date: 2016-04-26
CPC Classification: B22F,C21D,F27B,F27D

Claim Text:
1. A finish heat treatment method for an iron powder comprising: placing a raw iron powder on a continuous moving hearth; subjecting the raw iron powder to a pretreatment of heating the raw iron powder in an atmosphere of a hydrogen gas and/or an inert gas; and then continuously subjecting the pretreated iron powder to at least two treatments selected from decarburization, deoxidation, and denitrification to obtain a product iron powder, wherein: the hydrogen gas and/or the inert gas is used as ambient gas in the pretreatment and is introduced separately from ambient gas used in the at least two treatments, and the hydrogen gas and/or the inert gas in the pretreatment is introduced from an upstream side of a region where the pretreatment is performed and released from a downstream side of the region so that the gas flows in the same direction as a moving direction of the continuous moving hearth.