Method for making a magnet rotor assembly

Abstract

A method for making a magnet rotor assembly part by providing a bonded metal part having a determinable crush strength, impregnating the bonded metal part with a curable resin and curing the resin so that the crush strength of the assembly part is increased above the determinable crush strength both initially and after extended exposure to temperatures of at least 160° C. Improved crush strength in the magnet sleeve and in other bonded metal parts, both initially and after exposure to high temperatures is accomplished by impregnating the parts with a curable resin.

1 . A method for improving the crush strength of a bonded metal part comprising:
 Step (1) providing a bonded metal part having a determinable crush strength;   Step (2) impregnating the bonded metal part with a curable resin; and   Step (3) curing the resin whereby the crush strength of the part is increased above the determinable crush strength both initially and after extended exposure to temperatures of at least 160° C.   
     
     
         2 . The method of  claim 1  wherein the step of impregnating the bonded metal part with a curable resin comprises vacuum evacuation of gasses from the porosity in the bonded metal part and filling the porosity with the curable resin. 
     
     
         3 . The method of  claim 1  wherein the resin comprises a one-part Bisphenol A epoxy resin/amine hardener system. 
     
     
         4 . A method in  claim 1  producing a bonded metal part having improved crush strength both initially and after extended exposure to temperatures of at least 160° C. made by the method of  claim 1 . 
     
     
         5 . A method for making a bonded magnet having improved crush strength at elevated temperatures, the method comprising:
 Step (a) providing a sintered, compression molded or extruded bonded metal structure;   Step (b) impregnating the structure with an anaerobically curable resin system;   Step (c) curing the resin system; and,   Step (d) e-coating at least a portion of the surface of the magnet.   
     
     
         6 . The method of  claim 5  wherein the bonded metal structure comprises ferrite, samarium-cobalt, neodymium-iron-boron, alnico or mixtures thereof. 
     
     
         7 . The method of  claim 5  wherein the anaerobically curable resin is selected from the group consisting of methacrylate resin systems, phenol novolac resin systems, Bisphenol A modified phenol novolac epoxy resin systems, acid modified epoxy resin systems, urethane resin systems, polyester resin systems, and silicone resin systems. 
     
     
         8 . The method of  claim 5  wherein the anaerobically curable resin system is a methacrylate resin system. 
     
     
         9 . The method of  claim 5  wherein impregnating the bonded metal structure with an anaerobically curable resin system comprises vacuum evacuating gasses from the bonded metal structure.