| Summary: | 碩士 === 國立雲林科技大學 === 機械工程系碩士班 === 95 === This study investigates the effects of tin, range from 0.029 - 0.21wt%, hot-rolled finishing temperature and cold rolled annealing temperature on the texture and magnetic properties of four non-oriented electrical steels.
It is found that 5~10μm MnS precipitates is existed in the steel containing as the 0.029wt% tin. However, smaller 1-2μm AlN and MnS precipitates existed in the steel containing 0.21wt% tin. Therefore, tin can slow down the precipitation and coarsening of AlN and MnS. The recrystallization fraction of hot rolled bands also decreased with increasing tin in steels. During final cold rolled steel annealing, the nuclei formation were inhibited in the steel with increasing tin content. If lets Goss grain have the chance to growth rapidly in the steel containing higher tin. Therefore, after final annealing at 950℃, the grain size decreased with increasing tin content. On the other hand, the intensity of Goss texture increased with increasing tin content in steels.
The core loss decreased with tin content and become level off after tin reached 0.1wt%. Furthermore flux density increased with increasing tin content and become level off after tin reached 0.1wt%. Tin affects the magnetic properties of nonoriented electrical steels through the combination effects of changing the grain size and texture.
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