Inhibiting plastic tensile instability of non-symmetric thin-walled shell component via increasing regional metal inflow based on heterogeneous pressure-carrying medium  

作　　者：Nan XIANG Yiquan SHU Pengyi WANG Menghan YANG Haoran WANG Tao HUANG Junqing GUO Fuxiao CHEN 

机构地区：[1]School of Materials Science and Engineering,Henan University of Science and Technology,Luoyang 471023,China [2]National Key Laboratory for Precision Heat Processing of Metals,School of Materials Science and Engineering,Harbin Institute of Technology,Harbin 150001,China [3]College of Mechanical&Electrical Engineering,Shaanxi University of Science&Technology,Xi’an 710021,China [4]Provincial and Ministerial Co-construction of Collaborative Innovation Center for Non-ferrous Metal new Materials and Advanced Processing Technology,Luoyang 471023,China

出　　处：《Chinese Journal of Aeronautics》2024年第1期391-413,共23页中国航空学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(No.52275329,No.51905156,and No.51805309);Natural Science Foundation of Henan(No.232300421059);the fellowship of China Postdoctoral Science Foundation(No.2020M672221)。

摘　　要：Heterogeneous pressure-carrying medium was employed to establish a differentiated pressure field on sheet metal in flexible die forming process in this work,which aimed at matching the non-symmetric shape of target component and improving metal inflow to avoid local tensile instability.Specifically,metal inflow corresponding to the differentiated pressure field was analytically evaluated.Forming of a typical non-symmetric shell component was experimentally and numerically studied based on the proposed method.Compared with forming processes based on the uniform pressure,difference of metal inflow in two sides of the non-symmetric component increased from 2.16 mm to 3.36 mm and metal inflow in critical region increased by 11.9%when differentiated pressure field(taking heterogeneous elastomer#4–3 for example)was employed.The resultant maximum thinning ratio decreased by 4.2% and the uniformity of shell thickness increased by 16.9%.With the decrease of Shore hardness of elastomer in the formed region,stress path in the ready-to-form region transferred towards the bi-axial tension stress state,i.e.,stress ratio(a)increased.And,stress triaxiality(η)in characteristic regions were regulated appropriately,which decreased the risk of tensile instability.It was attributed to the decreased normal pressure and frictional resistance at sheet/elastomer interface in the formed region.

关 键 词：Aluminum alloys Finite element method Metal forming Plastic deformation Sheet metal 

分 类 号：TG146.21[一般工业技术—材料科学与工程]