(西北工業(yè)大學 凝固技術國家重點實驗室， 西安 710072)
摘 要: 在電磁約束成形中通過Aφ-A三維有限元法所得的磁感應強度、 渦流密度和集膚層厚度分布，求得電磁壓力的分布； 對具有不同寬厚比的帶圓角矩形截面樣件所受的電磁壓力進行了分析。 發(fā)現(xiàn)寬厚比越大的樣件， 相鄰兩邊電磁壓力之差也越大。 圓角形狀產(chǎn)生的渦流流向變化也能明顯改變樣件表面電磁壓力的分布，當圓角半徑接近或小于集膚層厚度時， 角部與直邊連接處形成一個電磁壓力衰減區(qū)， 這種電磁壓力分布規(guī)律極大地增加了大寬厚比小的圓角矩形樣件截面的成形難度。
關鍵字: 電磁約束成形; 電磁場; 電磁壓力; 數(shù)值模擬
（ State Key Laboratory of Solidification Processing, Northwestern Polytechnical University,
Xi’an 710072, China）
Abstract: The distribution of electromagnetic pressures is computed on magnetic induction intensity, eddy density, and skin depth, which are calculated by Aφ-A of 3-D FEM in electromagnetic confinement and shaping. The pressures on round-rectangle samples with different width-thickness ratio are analyzed. The higher the width-thickness ratio is, the higher the electromagnetic pressure differential between broad edge and narrow edge is. The direction change of eddy current coming from the angle structure changes the distribution of electromagnetic pressure. When the radius of round angle is close or little than skin depth, the electromagnetic pressure between the round angle and the straight edge will be attenuated. This distribution of electromagnetic pressure makes shaping the section with large width-thickness ratio and little round angle more difficult.
Key words: electromagnetic shaping; electromagnetic field; magnetic pressure; digital simulation
