The early detection of surface defects on raw sheet metal parts is a critical problem in the automotive industry. Typical defects like dents, bumps and waviness are invisible at the early production stages because of the parts’ rough surfaces. The defects become visible and disturbing only after the later production steps, in which the parts get painted and varnished, meaning that they become s...

Bending operations are frequently used to produce sheet metal components. Spring-back is an issue in sheet metal forming processes and some times is a principle problem for producing precise components. This is more important if some kind of cuttings exists on the bending surfaces. Experiments show that punched holes on bending surfaces affect the value of the spring-back. In this paper the spr...

Plasticine is widely used in the analysis of metal forming processes, due to its excellent material flow ability. In this study, plasticine is used as the soft punch to fabricate array micro-channels on metal sheet in the micro sheet stamping process. This is because plasticine can produce a large material flow after being subjected to force and through the material flow, the plasticine can cau...

This paper investigates the nesting issue and the machining path planning issue for improving the sheet metal machining efficiency. The nesting issue is to maximise sheet metal material utilisation ratio by nesting parts of various shapes into the sheet. The path planning issue is to optimise machining sequence so that the total machining path distance and machining time are minimised. This wor...

Laser forming is a flexible sheet metal forming technique using laser induced thermal distortion to shape sheet metal without hard tooling or external forces. Concave laser forming can be readily achieved, while convex forming could be done under buckling mechanism but whether convex forming is actually obtained heavily depends on the initial strain/stress state of the sheet. A new laser-scanni...

The r-value of a sheet metal is a measure of plastic anisotropy frequently used for prediction of performance in deep-drawing. It has also gured prominently in the literature for validation of theories where the predicted angular dependence of r is compared with the measured dependence. As plastic anisotropy in sheet metals is caused mainly by the preferred orientations of grains within the pol...

This paper describes an application of data mining, namely classification, with respect to 3-D surface analysis. More specifically in the context of sheet metal forming, especially Asymmetric Incremental Sheet Forming (AISF). The issue with sheet metal forming processes is that their application results in springback, which means that the resulting shape is not necessarily the desired shape. Er...

Abstract Laser forming is a flexible sheet metal forming technique using laser-induced thermal deformation to shape sheet metal without hard tooling or external forces. Concave laser forming can be readily achieved, while convex forming may occur through buckling, but the buckling direction heavily depends on the sheet surface and pre-strain condition. A new laser scanning scheme is postulated,...

Compared with the conventional manufacturing of aluminum sheet metal, the forming of so called Tailored Heat Treated Blanks (THTB) enables the production of complex aluminum sheet metal parts [1], [2]. The reasons for the lower forming behavior of aluminum alloys are well founded in the material properties. Especially smaller values for uniform elongation (< 30 %) and vertical anisotropy (< 1) ...