Summary: | 碩士 === 國立高雄第一科技大學 === 機械與自動化工程系先進製造科技碩士班 === 105 === The aim of this study is to build high efficiency and low iron loss deterioration on silicon steel (China Steel Corporation:50CS470、50CS1300&35CS210) with technology. In comparison to electro chemical machining, stamping process induces residual stress inside the material which deteriorates the iron loss property. Important parameters to decrease the deteriorated iron loss property are analyzed, including commonly adjusted trimming tolerance (10~25μm),stamping speed (250~510SPM) and blank hold force (635~3175Kgf). In addition annealing the process after stamping process. The results show: (1) 50CS470: the lowest percentage of iron loss deterioration is 10.1%, while 3.5% trimming tolerance and 10% blank hold force are applied. (2) 50CS1300: the lowest percentage of iron loss deterioration is 5.2%, while 2% trimming tolerance and 10% blank hold force. (3) 35CS210: the lowest percentage of iron loss deterioration is 46%, while 5% trimming tolerance and 12% blank hold force. (4) Iron loss property of silicon steel is affected by residual stresses and grain size, when annealing temperature is lower than 860℃, the effect of residual stress dominates and the iron loss property improve with the annealing temperature. With the optimum annealing condition of 860℃ holding temperature, 3 hours holding time at 5.5╳10-4Torr vacuum level, the iron loss is very close to electro chemical machining.(5) The grain size increases from 30~40μm to 65~70μm after stamping and the iron loss deterioration rate is from 10% to 21%.
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