PROCESS AND AN APPARATUS FOR PRODUCING LOW-OXYGEN IRON-BASE METALLIC POWDER

摘要

A process and an apparatus for producing low-oxygen iron-base metallic powder are disclosed. The low-oxygen ironbase metallic powder is produced in a shaft-type apparatus comprising a preheating zone and an induction heating zone by alloying and/or admixing iron-base metallic raw powder to be subjected to a final reduction, which has an apparent density corresponding to 16-57% of theoretical true density, an oxygen content of not more than 6% by weight and a particle size of not more than 1 mm, with carbon or carbonaceous granule in an amount corresponding to not more than an objective alloying carbon content of a final produce (% by weight) + an oxygen content of the powder just before the final reduction (% by weight) x 1.35 to form a starting powder, preheating the starting powder at a temperature of 780 - 1,130.degree.C in a nonoxidizing atmosphere having a theoretical oxygen partial pressure of not more than 2.1 x 10-1 mmHg and a dew point of not more than +5.degree.C in the preheating zone to form a preheated and sintered cake (P-cake), induction heating the P-cake at a temperature of 850 - 1,400.degree.C in the same atmosphere by applying an alternating power of 50 Hz to 500 kHz from power supply to effect deoxidation and decarburization to form an induction heated cake (I-cake), and then cooling and pulverizing the Icake.