With the development of modern industry, more and more permanent magnetic materials are used at elevated temperatures. Thus it has become more and more important to measure their magnetic properties accurately both at room temperature and elevated temperatures. In this paper, for a better understanding of temperature coefficients, measuring of the magnetic properties at elevated temperatures and related problems are reviewed and discussed qualitatively. Advices on magnetizing permanent magnets at elevated temperatures are also given. In addition, principal problems and new advances involved in measuring techniques at elevated temperatures are also discussed. Furthermore, problems associated with testing magnets at elevated temperatures using a vibrating sample magnetometer (VSM) are also presented.
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