Mechanical properties of hot-rolled Pr-Fe-B-Cu magnets

Abstract

Mechanical strength and properties of thin plates were investigated for hot-rolled Pr-Fe-B-Cu magnets. Tensile strengths of the hot-rolled magnets were more than 23.7 kg f/mm2. Bending tests were also applied and the strength of 37.7 kg f/mm2 was obtained. The strengths obtained are definitely higher than that of commercial Nd-based sintered magnets. It was found that the mechanical strengths were enhanced by Pr2Fe14B grain refinement caused by Cu addition. Related to high mechanical strength, hot-rolled Pr-Fe-B-Cu magnets show excellent machinability. Thin plate magnets up to 0.1 mm in thickness with fairly large surface area were produced without any cracking. Moderate energy products better than 20 MGOe were achieved by heat treatment after machining.