Summary: | 碩士 === 國立臺北科技大學 === 材料及資源工程系研究所 === 102 === This study for Fe-Si-Cr alloy powder phosphating,and add different amounts of sodium silicate granulated,forming,annealing,and then measure its magnetic properties and to observe the effect of the powder coated. SEM observation of the successful use of sodium silicate is coated on the powder surface state,among which sodium silicate added 4 wt% better surface condition. As the VSM data adding phosphoric acid and sodium silicate,the saturation magnetization of 191.38 emu / g dropped to 107.98 emu / g. From the salt spray test, we found that 2 % sodium silicate will produce rusty condition, while the amount of sodium silicate increased to more than 4 % will not rust. It can be found in the study, the more acid added, the more remarkable the effect of the phosphate coating to powder, resulting to improve the insulation resistance. Adding sodium silicate and more, have a higher insulation resistance. Permeability and quality factor in the analysis results, the preferred solution is 2 wt% phosphoric acid + 4 wt% sodium silicate, taking into account the resistance value, surface oxidation, permeability and quality factor.
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