Silicon steel is characterized by a high melting point,poor fluidity,and limited wettability,and the process window for the preparation of non-oriented silicon steel ribbons by planar flow casting(PFC)is limited.Durin...Silicon steel is characterized by a high melting point,poor fluidity,and limited wettability,and the process window for the preparation of non-oriented silicon steel ribbons by planar flow casting(PFC)is limited.During the production process,the melt puddle(MP)behavior is a key factor in determining the final quality of ribbons,and the influence mechanism of the airflow boundary layer on the MP behavior and the surface quality of ribbons is still unclear.The effects of wheel speed on the quality of PFC Fe–3.0%Si non-oriented silicon steel ultra-thin ribbons were systematically investigated.Combined with experiments and numerical simulations,the mechanism of different wheel speeds on the behavior of MP and the surface quality of ribbons was analyzed in depth.It is found that when the MP reaches a steady state,the upstream meniscus shows a C-shape,while the downstream meniscus exhibits a sloped shape.During the formation of the MP,the vortex phenomena occur both around and within the MP.With the increase in wheel speed,the thickness of the ribbons gradually decreases from 67 to 31μm.Furthermore,the air vortex on the upstream and downstream meniscus becomes more and more intense,which significantly increases the possibility of air entrapment in the MP and leads to a significant increase in the percentage of air pockets.When the wheel speed is 10–15 m/s,the surface of the ribbon is smooth,the thickness uniformity is better,and there are fewer defects.However,when the wheel speed is more than 15 m/s,the MP’s stability deteriorates,and the ribbons have obvious veining,wrinkles,and uneven thickness.展开更多
With the development of electronic components towards high frequency,high efficiency,and miniaturization,the demand for non-oriented silicon steel ultra-thin ribbons is increasing,which were usually prepared by multi-...With the development of electronic components towards high frequency,high efficiency,and miniaturization,the demand for non-oriented silicon steel ultra-thin ribbons is increasing,which were usually prepared by multi-pass rolling with complex processes and high cost.The ultra-thin non-oriented silicon steel ribbons with silicon content of 2–4.5 wt.%Si were prepared with the planar flow casting technology,and the microstructure and properties of ribbons were investigated.The results showed that as the silicon content increased,the grain size of the as-cast ribbons gradually decreased,and the dislocation density and internal stress were higher.The proportion of{100}oriented grains gradually increased from 29.3 to 37.3%,and the ratio of{110}and{111}oriented grains decreased.Meanwhile,the magnetic induction B50 showed a decline trend from 1.62 to 1.45 T with the increase in silicon content,while the iron loss P_(1.0/400) increased from 20.61 to 66.65 W/kg.This may be related to the silicon content affecting the wettability of melt and the wheel,thereby affecting the cooling capacity.The grains grew significantly after annealing,the internal stress was released and dislocations were eliminated.All this greatly improved the magnetic properties and decreased the hardness.B_(50) of ribbons with 2 wt.%Si reached 1.66 T and P_(1.0/400) of ribbons with 4.5 wt.%Si was reduced to 13.40 W/kg.The percentage of{110}fiber grains increased obviously while{100}fiber grains decreased slightly after heat treatment.展开更多
基金supported by the National Key Research and Development Program of China(No.2021YFB3800501)Numerical calculation in this research is supported by the High-Performance Computing Center of Wuhan University of Science and Technology.
文摘Silicon steel is characterized by a high melting point,poor fluidity,and limited wettability,and the process window for the preparation of non-oriented silicon steel ribbons by planar flow casting(PFC)is limited.During the production process,the melt puddle(MP)behavior is a key factor in determining the final quality of ribbons,and the influence mechanism of the airflow boundary layer on the MP behavior and the surface quality of ribbons is still unclear.The effects of wheel speed on the quality of PFC Fe–3.0%Si non-oriented silicon steel ultra-thin ribbons were systematically investigated.Combined with experiments and numerical simulations,the mechanism of different wheel speeds on the behavior of MP and the surface quality of ribbons was analyzed in depth.It is found that when the MP reaches a steady state,the upstream meniscus shows a C-shape,while the downstream meniscus exhibits a sloped shape.During the formation of the MP,the vortex phenomena occur both around and within the MP.With the increase in wheel speed,the thickness of the ribbons gradually decreases from 67 to 31μm.Furthermore,the air vortex on the upstream and downstream meniscus becomes more and more intense,which significantly increases the possibility of air entrapment in the MP and leads to a significant increase in the percentage of air pockets.When the wheel speed is 10–15 m/s,the surface of the ribbon is smooth,the thickness uniformity is better,and there are fewer defects.However,when the wheel speed is more than 15 m/s,the MP’s stability deteriorates,and the ribbons have obvious veining,wrinkles,and uneven thickness.
基金supported by the financial support from National Key Research and Development Program of China(No.2021YFB3800501)。
文摘With the development of electronic components towards high frequency,high efficiency,and miniaturization,the demand for non-oriented silicon steel ultra-thin ribbons is increasing,which were usually prepared by multi-pass rolling with complex processes and high cost.The ultra-thin non-oriented silicon steel ribbons with silicon content of 2–4.5 wt.%Si were prepared with the planar flow casting technology,and the microstructure and properties of ribbons were investigated.The results showed that as the silicon content increased,the grain size of the as-cast ribbons gradually decreased,and the dislocation density and internal stress were higher.The proportion of{100}oriented grains gradually increased from 29.3 to 37.3%,and the ratio of{110}and{111}oriented grains decreased.Meanwhile,the magnetic induction B50 showed a decline trend from 1.62 to 1.45 T with the increase in silicon content,while the iron loss P_(1.0/400) increased from 20.61 to 66.65 W/kg.This may be related to the silicon content affecting the wettability of melt and the wheel,thereby affecting the cooling capacity.The grains grew significantly after annealing,the internal stress was released and dislocations were eliminated.All this greatly improved the magnetic properties and decreased the hardness.B_(50) of ribbons with 2 wt.%Si reached 1.66 T and P_(1.0/400) of ribbons with 4.5 wt.%Si was reduced to 13.40 W/kg.The percentage of{110}fiber grains increased obviously while{100}fiber grains decreased slightly after heat treatment.
