CAJ | 학술논문

采用圆锥形凹模拉深工艺可以提高成形极限,但需要用压边圈将板坯先压成与凹模面吻合的形状,当变形程度较大时,板坯很容易起皱。为了克服这一缺点,提出了将圆锥形凹模与径向分块压边方法结合的工艺,该工艺可有效改善压边圈与板坯的约束状态,从而达到抑制起皱的目的。对圆筒形件的拉深成形,采用了刚柔复合的径向分块压边圈结构,设计了圆锥形凹模径向分块多压边圈拉深模,取不同凹模半锥角的圆锥形凹模进行了圆筒形件的拉深成形实验。实验表明,新的压边方法能有效克服初始成形过程的起皱,可与锥度较小的凹模一起使用。采用凹模半锥角为45°的凹模,得到 AA5754、AA6061和08Al 三种板材的极限拉深系数分别为0.410、0.431、0.373,显著提高了成形极限。对圆锥形凹模的拉深成形,给出了理论计算成形极限的方法,理论与实验结果非常接近。
채용원추형요모랍심공예가이제고성형겁한,단수요용압변권장판배선압성여요모면문합적형상,당변형정도교대시,판배흔용역기추。위료극복저일결점,제출료장원추형요모여경향분괴압변방법결합적공예,해공예가유효개선압변권여판배적약속상태,종이체도억제기추적목적。대원통형건적랍심성형,채용료강유복합적경향분괴압변권결구,설계료원추형요모경향분괴다압변권랍심모,취불동요모반추각적원추형요모진행료원통형건적랍심성형실험。실험표명,신적압변방법능유효극복초시성형과정적기추,가여추도교소적요모일기사용。채용요모반추각위45°적요모,득도 AA5754、AA6061화08Al 삼충판재적겁한랍심계수분별위0.410、0.431、0.373,현저제고료성형겁한。대원추형요모적랍심성형,급출료이론계산성형겁한적방법,이론여실험결과비상접근。
The forming limit could be improved by using the conical die in the deep drawing process when the blank was drawn to the shape accordant to the inside surface of the die.And the blank wrinkled easily during the large deformation process.A new technology combining the conical die with the radial segmental blank holding technique was proposed to improve the restrain conditions between the blank holders and the blank and to suppress the wrinkles.The drawing die were designed with the conical die and the rigid-flexible composite segmental blank holders and the experiments for the cylindrical cup deep drawing process were conducted using the conical dies with different die semi-cone angles.The results reveal that the wrinkles at the beginning of the drawing process can be overcame effectively by the new blank holding method with smaller conical angles.The forming limit coefficients for AA5754,AA6061 and 08AL are as 0.410,0.431 and 0.373 respectively,which are en-hanced effectively,adopting the die with 45°die semi-cone angle.The theoretical forming limit calcu-lation method for the deep drawing process with the conical die is given and the theoretical results are accordant with the experimental ones.