PURPOSE: To obtain excellent magnetic properties of a rare earth metal magnet in internal coercive force and remaining magnetic flux density by containing more than one type of rare earth metal elements and pulverizing alloy powder of Co, Fe, etc. into 100W9,000.

CONSTITUTION: Metal Sm (99.9%>) of approx. 36.5wt% and metal Co (99.99%>) of approx. 63.5wt% are molten in argon atmosphere, and an alloy ingot is manufactured. Then, the ingot is roughly pulverized by a crusher. This alloy powder is then pulverized by a conventional method such as a ball mill, a vibration mill or a jet mill into approx. 3W6μm in particle size. On the other hand, ultrafine powder is produced by a vacuum deposition method. The grain size is 100W 9,000. All above powders are compression molded by 1.5ton/cm2 in a magnetic field of 15,000 oersted, and secondarily compressed by 10tons/cm2 of a hydrostatic pressure in rubber. This is sintered at respective sintering temperatures, and then heat treated at approx. 850°C for approx. 1hr. In this manner, excellent magnetic properties in both internal coercive force and remaining magnetic flux density can be obtained.