Plastic instability conditions in the deep-drawing of a circular blank of sheet metal

Deep spinning of sheet metals

“…16. Comparing to other achieved spinning ratios, deep spinning not only surpassed the previously achieved spinning ratios, but also, significantly surpassed the deep drawing process [14] as shown in Fig. 16.…”

“…The achieved LSRs for small values of (d m /t b ) are lower than those obtained in conventional deep drawing, which is usually higher than 2.0 [14]. Furthermore, for higher values of (d m /t b ) the difference becomes much wider.…”

“…This is slightly wider than that in deep drawing [14] to ease the flange relative rotation inside the deformation zone.…”

“…In the current study, a roller nose radius R r is initially chosen to be 9.0 mm, which is six times the original blank thickness. This nose radius size is slightly less than the recommended die profile in deep drawing [14] to ensure spinning ratio for the free flange less than 1.4. Then two rollers with larger and smaller nose radii of 12.0 mm and 6.0 mm, respectively are tested to investigate the effect of roller nose radii on the formability of the new deep spinning process.…”

“…Fig. 1 summarizes the maximum achieved LSRs of conventional spinning of commercial pure aluminum sheet metals for the previous studies [5][6][7][8]12,13] and that for conventional deep drawing [14] at various mandrel diameter to blank thickness ratios…”