| The influnence of coupling agent, binders, curing process , formation process and the size of NdFeB powder on NdFeB bonded magnet has been systematically studied by a lot of experiments.The bonded magnet from rapid quenched NdFeB has been produced, and the influence of the technique factors such as coupling agent, coupling process, powder particle size ,binder, solidification process, formation process on its properties has been analysised by means of SEM, DGN-3 magnetic properties analysis, compressive strength measurement, etc . From a lot of tests, the bonded NdFeB magnet with high properties have been prepared by rapid quenched powder, and the mechanic and magnetic properties with Br=0.568T, Hcj=836 kA . m-1, (BH)max=55 kJ . m-3, compressive strength is 148MPaIt has shown that if the combination with higher magnetic and mechanic properties of the bonded magnet is wanted , titanate coupling agent is more proper than silane coupling agent. At the same time ,the result show that the particle size and distribution of rapidly quenched NdFeB magnetic powder affect obviously on the magnetic property of the bonded NdFeB magnets. From the analysis of the relationship between different particle size and the magnetic properties, the proportion of the particle size with 147um, 100um and 74um is 8:62:30, can get the better results.Solid epoxy resin with the low epoxy value is better than liquid epoxy resin to the magnetic performance, and the content is 2%wt will do good to improve the magnetic characteristics of the bonded NdFeB magnet. So if compound the epoxy resin and the W-6A magnetic powder binders as the new binder,the results of the test is greatly better than the former test.It has shown that the combination with higher magnetic and mechanic properties of the bonded magnet is presented on the basis of proper curing process temperature, 120 Cto 150 C,and the curing agent is and proper mold press, 500-600MPa, keeping press time is 20 seconds.
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