Rare earth magnet alloy ingot, manufacturing method for the same, R-T-B type magnet alloy ingot, R-T-B type magnet, R-T-B type bonded magnet, R-T-B type exchange spring magnet alloy ingot, R-T-B type exchange spring magnet, and R-T-B type exchange spring bonded magnet

摘要

One object of the present invention is to provide a rare earth magnet alloy ingot, which has improved magnetic properties. In order to achieve the object, the present invention provides a rare earth magnet alloy ingot, wherein the rare earth magnet alloy ingot comprises an R-T-B type magnet alloy (R represents at least one element selected from among rare earth elements, including Y; and T represents a substance predominantly comprising Fe, with a portion of Fe atoms being optionally substituted by Co, Ni, Cu, Al, Ga, Cr, and Mn.) containing at least one element selected from among Nd, Pr, and Dy in a total amount of 11.8 to 16.5% by atom and B in an amount of 5.6 to 9.1% by atom; and wherein as determined in an as-cast state of the alloy ingot, R-rich phase that measures 100 μm or more is substantially absent on a cross section.