Cold piercing of magnesium alloy billet with high aspect ratio
Cold piercing of magnesium alloy billet with high aspect ratio
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高长径比镁合金坯料冷穿孔
DOI：
10.1016/j.ijmachtools.2005.07.039
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发表时间：
2006
影响因子：
14
通讯作者：
K. Osakada
中科院分区：
文献类型：
--
作者：
R. Matsumoto;T. Kubo;K. Osakada
在室温下通过施加反压力对镁合金AZ 31 B（Mg-3%Al-1%Zn）的圆柱形坯料进行穿孔，以形成纵横比（初始坯料高度/穿孔冲头直径）大于1.0的孔。在穿孔期间，坯料保持在容器中，并且反压力由反冲头从穿孔冲头的相对侧施加到坯料。研究了模具间隙和反压力对孔表面质量的影响。在无反压力冲孔的情况下，无论冲头和冲模之间的间隙如何，孔表面都由于断裂而非常粗糙。当施加高反压力时，获得具有良好剪切表面质量的孔。施加反压力后，由于变形方式由纯剪切变形转变为正-反挤压复合变形，穿孔坯料的高度略有提高，而从孔中喷出的塞料高度降低。
Cylindrical billet of a magnesium alloy AZ31B (Mg–3%Al–1%Zn) is pierced at room temperature by applying counter pressure to make a hole of an aspect ratio (initial billet height/piercing punch diameter) greater than 1.0. During piercing, the billet is kept in a container and the counter pressure is applied to the billet by a counter punch from the opposite side of the piercing punch. The effects of die clearance and counter pressure on the quality of the created hole surface are examined. In the case of piercing without counter pressure, the hole surface is very rough due to fracture irrespective of the clearance between the punch and the die. When a high counter pressure is applied, a hole with good shear surface quality is obtained. By applying the counter pressure, the height of the pierced billet becomes slightly higher and the height of the slug ejected from the hole becomes lower because of the change of the deformation mode from pure shear deformation to combined forward–backward extrusion.