| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for manufacturing a rare-earth magnet, capable of manufacturing a bulk magnet using HDDR powders at the higher efficiency than conventionally.SOLUTION: The method for manufacturing the rare-earth magnet includes the steps of: forming the HDDR powders to manufacture a green compact; heating the green compact up to a given temperature in a range of 500 to 900°C at a temperature rising speed of 5°C/sec or more; pressurizing the green compact at a pressure of 20 to 3,000 MPa so that a period in which a value of time differential of a dimensional change in a pressurizing direction of the green compact when the pressurizing direction is positive is -0.12 to 0.0 mm/min or less is less than 90 seconds while the green compact is at the given temperature, thereby obtaining a bulk body having density of ≥7.52 g/cm; cooling the bulk body from the given temperature down to a temperature of <400°C; and performing heat treatment ranging over time of ≥1 min and <60 min at a first temperature of 500 to 900°C in a vacuum or inactive atmosphere without pressurizing the bulk body. |
