Abstract Ultrasonic flexible bulging process based Ethylene-vinyl acetate (EVA) soft medium is presented for fabricating the surface texturing with 3 dimensional shape using ultra-thin metallic sheet of 50 μm in thickness. Advantages of ultrasonic vibration and flexible forming are both utilized to guarantee the forming quality of big area surface texturing, i.e. spherical caps. Effects of ultrasonic vibration, such as amplitude and duration time, were investigated, and compared between flexible and rigid punch. Experimental results show that the ultrasonic flexible bulging can improve the surface quality and increase the height of bulged cap and length of intersection edge. Analysis and discussion of ultrasonic flexible bulging mechanism are carried out from the viewpoint of stress states of ultra-thin sheet in bulging process by considering the acoustic softening effects and abilities of EVA soft medium in uniformly transmitting pressure. The results reveal that the proposed process is suitable to manufacture the complex surface texture of ultra-thin metallic sheet with high quality.

中文翻译：

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5052铝合金超薄板表面织构球冠阵列超声柔性胀形工艺

摘要 提出了基于乙烯-醋酸乙烯酯（EVA）软介质的超声波柔性膨胀工艺，用于使用厚度为 50 μm 的超薄金属片制造具有 3 维形状的表面纹理。利用超声波振动和柔性成型的优点，保证大面积表面织构即球冠的成型质量。研究了超声波振动的影响，如振幅和持续时间，并在柔性和刚性冲头之间进行了比较。实验结果表明，超声波柔性胀形可以提高表面质量，增加胀形帽的高度和相交边缘的长度。从超薄板在胀形过程中的应力状态，考虑EVA软介质的声软化效应和均匀传递压力的能力，对超声柔性胀形机理进行了分析和讨论。结果表明，所提出的工艺适用于制造高质量的超薄金属板的复杂表面纹理。