Dowa Mining Co., Ltd.

Toshinori Eba

Kiyoshi Yamada

Hirofumi Takei

Masami Kamada

A surface grinding machine for a sintered rare earth magnetic alloy wafer comprises a pair of disk-shaped grindstones that face each other across a prescribed gap to be rotatable in opposite directions about their center axes. The grinding surfaces of the pair of grindstones and the center axe inclination of one grinding stone are configured to form a planar grinding region A wherein a portion of both of the grinding surfaces of the pair of grindstones lie parallel with a constant intervening gap therebetween. Other portions of the grinding surfaces of the grindstones constitute a wedge-like opening region B that becomes more narrow toward the planar grinding surface A. A feeder to feed the wafers from the wedge-like opening region B toward the planar grinding region A is provided in order to grind both surfaces of the wafers at the planar grinding.

Sintered rare earth magnetic alloy wafer surface grinding machine

A method of producing a sintered rare earth magnetic alloy wafer comprises a step of using a cutter to slice a wafer of a thickness of not greater than 3 mm from a sintered rare earth magnetic alloy having ferromagnetic crystal grains surrounded by a more readily grindable grain boundary phase and a step of surface-grinding at least one cut surface of the obtained wafer with a grindstone to form at a surface layer thereof flat ferromagnetic crystal grain cross-sections lying parallel to the wafer planar surface. The method enables high-yield production of a sintered rare earth magnetic alloy wafer having flat surfaces.

Growing community of inventors

Obanazawa, Japan

Toshinori Eba