Study on Effecting Parameters of Flat and Hemispherical end Tools in SPIF of Aluminium Foils

Abstract

Single Point Incremental Forming (SPIF) is a fast technique in the range of flexible prototype production without using a punch or die. Absence of the molding tools makes SPIF useful to form a complex product and these parts usually need different tool shapes. The aim of this study was to compare the performance of flat end and hemispherical end tools in micro-SPIF and evaluate the threshold value of the tool radius in relation to initial blank thickness. This paper investigated the best results of the final geometry, thickness homogeneity, minimum pillow surface, and maximum forming depth using different shapes and different sizes of the tool. The analysis of the results on AlMn1Mg1 foils with 0,22 mm initial thickness shows that the flat tool improves the geometry accuracy and decreases the pillow effect. Furthermore, in micro-ISF higher formability and more stable thickness distribution can be achieved with a flat end tool.

Keywords

• aluminium alloy foils
• flat tool
• incremental forming
• pillow surface
• sheet forming
• single point