静压支撑单点渐进成形厚向应变分布研究

Study on Thickness-strain Distribution in Single-point Incremental Forming with Hydrostatic Supporting

采用单点渐进成形技术单道次成形复杂形状的薄壁零件时,厚度分布不均匀及过度减薄易于引起板材的断裂和成形失效。将静压支撑引入单点渐进成形中,形成一种静压支撑单点渐进成形工艺;通过促进材料流动和厚向应变分布来提高板材厚度分布的均匀性。选用初始厚度为1 mm的1060铝板,以静压支撑单点渐进成形的圆锥台件为研究对象,通过数值模拟和实验研究分析了静压参数对厚向应变分布和材料流动规律的影响。结果表明:0~0.18 MPa的静压支撑有利于过渡变形区Ⅱ的快速成形,有利于主变形区Ⅲ的厚向应变分布;在有利压力范围内,静压压力越大,由Ⅱ区流向Ⅲ区的材料越多,厚向应变分布越均匀,制件成形性能越好。

Uneven thickness distribution and excessive thinning easily lead to sheet fractures and forming failures when forming thin-walled parts with complex shapes in a single pass by using single-point incremental forming process.Hydrostatic supporting was introduced into the single-point incremental forming,and a single-point incremental forming process with hydrostatic supporting was formed;the uniformity of the sheet thickness distribution was improved by promoting material flow and thickness strain distribution.The 1060 aluminum sheets with an initial thickness of 1mm were selected,and the hydrostatically supported single-point incremental forming conical parts were taken as the research objects,and the influence of the hydrostatic parameters on the thickness strain distribution and material flow laws were analyzed by using numerical simulation and experiments.The results show that hydrostatic supports of 0-0.18 MPa are favorable to the rapid forming in the transition deformation zone II and the thickness strain distribution in the main deformation zone III;within the favorable pressure range,the higher the hydrostatic pressure,the more material flows from zone II to zone III,the more uniform the thickness strain distribution and the better the forming performance of the parts.