TA15合金H型构件等温局部加载成形工艺研究

基于DEFORM3D平台,建立筋板类构件等温局部加载宏微观有限元模型,对TA15钛合金H型构件等温局部加载成形工艺进行研究,揭示了局部加载过程中加载模式、分模面位置、加载次序及加载参数对筋的充填和初生α相晶粒尺寸的影响规律.结果表明:分模面位置设在筋上比设在腹板上的筋充填性好,初生α相晶粒尺寸分布均匀;相对于只采用局部加载成形,先局部加载后整体精整使得变形更均匀,筋的充填差较小并且流线分布更合理;改变局部加载成形参数,即增大横向筋和腹板、纵向筋和腹板之间的圆角半径,分模面处的纵向筋和横向筋的充填深度差增大;增加上模压下速度,使筋的充填深度减小,初生α相晶粒尺寸减小,但分布越来越不均匀;在两相区成形加载次序对初生α相的晶粒尺寸影响不显著.

H-Shaped Component Isothermal Local Loading Forming of TA15 Titanium Alloy

Based on the DEFORM-3D software, a finite element model considering macro-micro forming of rib-web component isothermal local loading has been established. The forming process of H-shaped component and the effects of loading mode and sequence, position of die partition, and process parameters on the filling of ribs and primary a-phase grain size have been investigated. The results show that the position of die partition has a significant effect on the filling of rib, the rib will be filled better and the distribution of primary a-phase grain size is more uniform when the die is partitioned along the rib. Comparing with only by local loading forming mode and through local loading combining with sizing forming, the deformation is more uniform and the difference of filling depths between ribs is smaller with better distribution of streamline. Enlarging the fillet radius between rib and web, the rib is filled well and the filling depth difference between transverse and longitudinal ribs increases. With the increase of loading speed, the filling depth of rib decreases, and the primary a-phase grain size decreases, but the distribution of primary a-phase grain size is more non-uniform. But the loading sequence has little effect on primary a-phase grain size