Forming Limit Stress Diagram Prediction of Aluminum Alloy 5052 Based on GTN Model Parameters Determined by In Situ Tensile Test

作     者：HE Min LI Fuguo WANG Zhigang 

作者机构：School of Materials Science and Engineering Northwestern Polytechnical University Xi 'an 710072 China Department of Mechanical Science and Engineering Xuzhou Institute of Technology Xuzhou 221008 China Department of Aircraft Structure Design and Research the First Aircraft Institute Aviation Industry Corporation of China Xi 'an 710089 China 

出 版 物：《Chinese Journal of Aeronautics》 (中国航空学报（英文版）)

年 卷 期：2011年第24卷第3期

页      面：378-386页

核心收录：

学科分类：080503[工学-材料加工工程] 08[工学] 081401[工学-岩土工程] 0805[工学-材料科学与工程（可授工学、理学学位）] 0802[工学-机械工程] 0825[工学-航空宇航科学与技术] 0814[工学-土木工程] 0801[工学-力学（可授工学、理学学位）] 080201[工学-机械制造及其自动化] 

基　　金：Aeronautical Science Foundation of China (03H53048) 

主　　题：forming limit stress diagram GTN model in situ tensile test void damage aluminum alloy 5052-O1 sheet metal forming 

摘      要：The conventional forming limit diagram （FLD） is described as a plot of major strain versus minor strain. However, FLD is dependent on forming history and strain path. In the present study, a forming limit stress-based diagram （FLSD） has been adopted to predict the fracture limit of aluminum alloy （AA） 5052-O1 sheet. Nakazima test is simulated by plastic constitutive formula derived from the modified Gurson-Tvergaard-Needleman （GTN） model. An in situ tensile test with scanning electron microscope （SEM） is proposed to determine the parameters in GTN model. The damage evolution is observed and recorded, and the parameters of GTN model are identified through counting void fraction at three damage stages of AA5052-O 1. According to the experimental results, the original void volume fraction, the volume fraction of potential nucleated voids, the critical void volume fraction, the void volume fraction at the final failure of material are assigned as 0.002 918, 0.024 9, 0.030 103, 0.048 54, respectively. The stress and strain are obtained at the last loading step before crack. FLSD and FLD of AA5052-O 1 are plotted. Compared with the experimental Nakazima test and uniaxial tensile test, the predicted results show a good agreement. The parameters determined by in situ tensile test can be applied to the research of the forming limit for ductile metals.