关键词: 渐进成形, 液压支撑, 临界角, 壁厚分布

Abstract: Uneven thickness distribution was the main reason for affecting product performance and forming quality when single-point incremental forming the thin-walled parts with complex shapes. Hydraulic supporting was introduced into the single-point incremental forming process, and a hydraulically supported single-point incremental forming process was proposed, uniform distribution of thickness was promoted by adding flexible support to the overhanging sheets. Conical parts with different wall angles were formed by single-point incremental forming of Al1060 sheets under the auxiliary supports of hydrostatic and variable pressure, the effects of hydrostatic parameters and variable pressure schemes on the thickness distribution and the critical angle of thickness uniformity were quantitatively analyzed through numerical simulations and experimental studies. The results show that the favorable hydrostatic pressure range is as 0~0.18 MPa for the critical angles of uniform thickness distribution, and the most favorable hydrostatic pressure value is as 0.17 MPa. Compared with unsupported single-point incremental forming, the hydraulically-supported single-point incremental forming process may increase the critical angle of thickness uniformity by 7°, which effectively improves the uniformity of thickness distribution and forming performance of the sheets.

Key words: incremental forming, hydraulic support, critical angle, thickness distribution