New resin-bonded Sm<inf>2</inf>Co<inf>17</inf>type magnets

Abstract

This report is related to the properties of the resin-bonded magnets. Some properties of these magnets are similar to those of SmCo <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</inf> sintered magnets. These resin-bonded magnets are made from Sm(Co Cu Fe Zr) <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">8.35</inf> alloys. In order to attain the alloys magnetically harden, heat treatments are done with cast alloys under bulk condition. There after ingots of the alloys are pulverized. The magnetic powder is mixed with resin binder or the lubricating binder. The mixture is compacted in the magnetic field. If the lubricating binder is used, the resin is penetrated into green body after compacting. After that the resin in the magnet is cured. Recently we have found the alloy of Sm(Co <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.672</inf> Cu <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.08</inf> Fe <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.22</inf> Zr <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.028</inf> ) <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">8.35</inf> with a good magnetic properties.[1] In order to obtain better magnetic properties we have been studying the alloys which contain more iron than that of the above alloy. As a result, the latter alloys were found to be also good materials for the magnet. Maximum iron content was about 22 wt%. It was realized that the resin-bonded magnet was able to have a high Br over 9KG. This magnet is suitable for applications which require high permeance coefficients.