Modelling of ductile fracture in single point incremental forming using a modified GTN model
Modelling of ductile fracture in single point incremental forming using a modified GTN model
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DOI：
10.1016/j.engfracmech.2017.09.021
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发表时间：
2017-12-01
影响因子：
5.4
通讯作者：
McCartney, Graham
中科院分区：
文献类型：
--
作者：
Gatea, Shakir;Ou, Hengan;McCartney, Graham
了解单点渐进成形（SPIF）的变形和破坏机理，对于提高成形性能具有重要意义。此外，将有更多的好处，更深入地评估局部变形的影响，在SPIF的断裂机制。尽管近年来已经进行了广泛的研究，但SPIF工艺中的剪切，特别是其对成形性的影响仍然存在问题。在这项工作中，一个改进的Gurson-Tvergaard-Needleman（GTN）损伤模型的发展与考虑剪切预测韧性断裂的SPIF过程中由于空洞的形核和合并的结果与原始GTN模型在SPIF。实验测试和SPIF处理相结合的方法被用来验证剪切修正的Gurson-Tvergaard-Needleman损伤模型的有限元结果。结果表明，在剪切加载条件下，剪切修正的GTN模型比原GTN模型提高了裂缝的模拟精度。此外，剪切作用下的横向拉伸应力起作用，加速SPIF过程中的断裂扩展。(C)2017作者由爱思唯尔有限公司发布
Understanding the deformation and failure mechanisms in single point incremental forming (SPIF) is of great importance for achieving improved formability. Furthermore, there will be added benefits for more in depth evaluation of the effect of localised deformation to the fracture mechanism in SPIF. Although extensive research has been carried out in recent years, questions still remain on the shear and particularly its effect to the formability in SPIF processes. In this work, a modified Gurson-Tvergaard-Needleman (GTN) damage model was developed with the consideration of shear to predict ductile fracture in the SPIF process due to void nucleation and coalescence with results compared with original GTN model in SPIF. A combined approach of experimental testing and SPIF processing was used to validate finite element results of the shear modified Gurson-Tvergaard-Needleman damage model. The results showed that the shear modified GTN model improved the modelling accuracy of fracture over the original GTN model under shear loading conditions. Furthermore, the shear plays a role under meridional tensile stress to accelerate fracture propagation in SPIF processes. (C) 2017 The Authors. Published by Elsevier Ltd.