上海第二工业大学学报
上海第二工業大學學報
상해제이공업대학학보
JOURNAL OF SHANGHAI SECOND POLYTECHNIC UNIVERSITY
2012年
1期
12-19
,共8页
液压成形%破裂:皱纹%管件
液壓成形%破裂:皺紋%管件
액압성형%파렬:추문%관건
hydroforming%burst%wrinkles%tube
针对双锥形管液压成形过程,分析了破裂和皱纹产生的几何及力学原因,并用数值模拟和工艺实验进行了验证。研究结果表明,有益皱纹需要同时满足几何条件和力学条件。几何条件是补料结束时形成的局部皱纹表面积略小于零件相应的表面积。力学条件是皱纹形状参数G不小于中间皱峰半径R,皱峰在后续高压整形过程中壁厚无减薄。当几何条件不满足时,即坯料任一段表面积大于零件相应表面积会起皱,过小会破裂;当力学条件不满足时,整形过程中中间皱峰发生开裂。
針對雙錐形管液壓成形過程,分析瞭破裂和皺紋產生的幾何及力學原因,併用數值模擬和工藝實驗進行瞭驗證。研究結果錶明,有益皺紋需要同時滿足幾何條件和力學條件。幾何條件是補料結束時形成的跼部皺紋錶麵積略小于零件相應的錶麵積。力學條件是皺紋形狀參數G不小于中間皺峰半徑R,皺峰在後續高壓整形過程中壁厚無減薄。噹幾何條件不滿足時,即坯料任一段錶麵積大于零件相應錶麵積會起皺,過小會破裂;噹力學條件不滿足時,整形過程中中間皺峰髮生開裂。
침대쌍추형관액압성형과정,분석료파렬화추문산생적궤하급역학원인,병용수치모의화공예실험진행료험증。연구결과표명,유익추문수요동시만족궤하조건화역학조건。궤하조건시보료결속시형성적국부추문표면적략소우령건상응적표면적。역학조건시추문형상삼수G불소우중간추봉반경R,추봉재후속고압정형과정중벽후무감박。당궤하조건불만족시,즉배료임일단표면적대우령건상응표면적회기추,과소회파렬;당역학조건불만족시,정형과정중중간추봉발생개렬。
Firstly, the geometry condition and the stress condition of the bursting and wrinkles during the hydroforming of double-cone tube were given. Then the analytical results were compared with the FEM analysis and experiments results. The results show that the useful wrinkles must meet both the geometry condition and the stress condition. The geometry condition of useful wrinkles is that the area ofworkpiece in the local zone at the end of axial feeding is close to the area of the corresponding part. The stress condition of useful wrinkles is that shape parameter G is not smaller than the radius R at the top of middle wrinkle. That means the increment of thickness strain det is positive and no thickness thinning will occur during the calibration. When the wrinkles didn't match geometry condition, the dead wrinkles and the bursting will take place. And when the wrinkles didn't match stress condition, the bursting at top of middle wrinkle will occur during the calibration.