摘要 |
PROBLEM TO BE SOLVED: To provide a rare earth based alloy in which an α-Fe volume fraction can be reduced as is in a cast state and the time required for heat treatment can be reduced in an R-T-B based alloy with the content of all rare earth elements being 13.0 atom% or less, and a method for manufacturing the same.SOLUTION: The rare earth based alloy is manufactured by a rapid solidification method using a quenching roll from an R-T-B based molten alloy with the content of all the rear earth elements being 13.0 atom% or less, wherein the α-Fe volume fraction is 1% or less. In this rear earth based alloy, by setting an R-rich phase interval to 10 μm or more, in a state of subjecting the alloy to heat treatment for heating the alloy to 1,135°C under an inert atmosphere or under reduced pressure and cooling the alloy after holding the alloy for 10 hours at the temperature, the R-rich phase interval can be made 70 μm or more, and the time required for the heat treatment can be remarkably shortened. |