Quenched alloy for rare earth magnet and a manufacturing method of rare earth magnet

A manufacturing method of rare earth magnet, comprising:

• coarsely crushing a quenched alloy for rare earth magnet to generate a powder, wherein:
• the quenched alloy comprises an R2T14B main phase,
• R is selected from at least one rare earth element comprising Nd,
• an average grain diameter of a primary crystallization in a brachyaxis direction is in a range of 10.21-14.88 μm,
• an average interval of a Nd rich phase is in a range of 1.15-2.77 μm,
• the quenched alloy has an average thickness in a range of 0.2-0.4 mm,
• counted in weight percent, more than 95% of the quenched alloy has a thickness in a range of 0.1-0.7 mm,
• a raw material of the quenched alloy comprises:
• R:
• 13.5 at %-15.5 at %,
• B:
• 5.2 at %-5.8 at %,
• Cu:
• 0.1 at %-0.8 at %,
• Al:
• 0.1 at %-2.0 at %,
• an atomic percent of W is in a range of 0.0005 at %-0.03 at %,
• T:
• 0 at %-2.0 at %, T is selected from at least one of the elements Ti, Zr, V, Mo, Co, Zn, Ga, Nb, Sn, Sb, Hf, Bi, Ni, Si, Cr, Mn, S or P, and
• remaining components comprise Fe and unavoidable impurity, and
• the quenched alloy is obtained by strip casting a molten alloy fluid of the raw material and cooling at a cooling rate between 102° C./s and 104° C./s;
• finely crushing the powder to fine powder;
• placing the fine powder under a magnetic field for pre-orientating and obtaining green compacts under a magnetic field;
• and
• sintering the green compacts in vacuum or in inert gas atmosphere in a temperature of 900° C.-1100° C.