局所摩擦加熱重ねインクリメンタルフォーミングによるアクリル板の金型フリー成形

抄録

A new forming method for PMMA sheets using friction stir incremental forming was proposed. In this method, A5052 sheet, A1050 sheets and PMMA sheets were overlapped and formed. Two types of PMMA sheets, extruded and cast ones, were employed for specimen. The size of these sheets were 185 mm x 185 mm and thickness were 0.5, 0.2 and 2 mm. A hemispherical tool with a diameter of 6 mm was used. The tool was rotated at 6000 - 12000 rpm and moved at 1000 – 4000 mm/min and sheets were formed into a frustum of conical shape which height of 40 mm and wall angle of 25 ° - 45 °.Formed shape was compared with the ideal shape. The specimen temperature during forming was measured using an infrared camera. Surface roughness of the extruded sheet was Ra = 4.45 μm, Rz = 25.89 μm, and that of cast sheet was Ra = 0.46 μm, Rz = 2.56 μm. The surface roughness of the cast sheets was about one tenth of that of the extruded sheets.