Measurement of radiation-induced demagnetization of NdFeB permanent magnet material for ERL undulators
نویسنده
چکیده
The note describes measurement of NdFeB permanent magnet (PM) material demagnetization induced by high-energy electron radiation. In experiments we compared N40 and N40SH grades from Stanford Magnets Company, which have different intrinsic coercive forces. Dimensions of the tested PM blocks were close to those that will be used for ERL undulator construction. It was found that depending on direction of magnetization, N40SH grade PM blocks are suffered 1% demagnetization when irradiated with 2.5Mrad or with 11.3Mrad dose from 5GeV electron beam. Setup, measurement technique, results and analysis are presented.
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تاریخ انتشار 2007