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论文类型：期刊论文

发表时间：2018-07-01

发表刊物：INTERNATIONAL JOURNAL OF MATERIAL FORMING

收录刊物：SCIE、Scopus

卷号：11

期号：4

页面范围：527-539

ISSN号：1960-6206

关键字：GTN damage model; Shear modification; Stress triaxiality; Sheet metal forming; Numerical simulation

摘要：Gurson-type models have been widely used to predict failure during sheet metal forming process. However, a significant limitation of the original GTN model is that it is unable to capture fracture under relatively low stress triaxiality. This paper focused on the fracture prediction under this circumstance, which means shear-dominated stress state. Recently, a phenomenological modification to the Gurson model that incorporates damage accumulation under shearing has been proposed by Nahshon and Hutchinson. We further calibrated new parameters based on this model in 22MnB5 tensile process and developed the corresponding numerical implementation method. Lower stress triaxiality were realized by new-designed specimens. Subsequently, the related shear parameters were calibrated by means of reverse finite element method and the influences of new introduced parameters were also discussed. Finally, this shear modified model was utilized to model the small punch test (SPT) on 22MnB5 high strength steel. It is shown that the shear modification of GTN model is able to predict failure of sheet metal forming under wide range of stress state.