Abstract
Thin-walled metal parts with functional micro-featured surface have broad application prospects in the fields of resistance reduction,noise reduction,etc.In this study,a novel micro-rolling & incremental sheet forming hybrid process(μR-ISF)is proposed to fabricate thin-walled metal parts with microgroove arrays.An analytical model which relates the rolling force and micro-groove depth in the micro-rolling stage was first established.Then,the formation mechanism of microgroove morphology during both micro-rolling stage and macro-shape forming stage are inves-tigated.After the micro-grooved sheet being incrementally formed,a significant reduction(between 21％to nearly 60％)is occurred in the depth of both transverse and longitudinal grooves compared to the flat sheet.Meanwhile,the width of transverse grooves decreases slightly by about 10％on average,while the width of longitudinal microgrooves increases significantly by more than 30％on average.After micro-rolling,85°{ 1012} tensile twins appear on the micro-grooved sheet and the percentage of 65°{1122} compressive twins increases.After incremental forming,the percentage of low-angle grain boundaries and the density of geometrically necessary dislocations in the formed part increase significantly,and the grain size distribution becomes more uniform.The present work provides a new strategy for the fabrication of 3D metal thin-walled components with surface micro-features.
基金项目
National Natural Science Foundation of China(51975328)
National Natural Science Foundation of China(52275348)
Taishan Scholar Project of Shandong Province(tsqn202306006)
Youth Innovation Technology Support Program of Shandong Provincial Universities(2022KJ041)
万方数据