This paper aims to present a Continuum Damage Mechanics based fracture model. Two yield surfaces, plastic and damage, are utilized to develop the model. A modified ductile fracture model coupling both stress triaxiality and Lode angle parameter is then proposed. The proposed model is applied to construct the fracture loci of four types of metal alloys: steel HY100, steel PCrNi3MoVA, aluminum 2024-T351, steel TRIP690 and steel A533B. The prediction is also involved investigation of the dependency of damage evolution on stress triaxialities for steel HY100 and steel A533B. The new model is also utilized to construct the Fracture Forming Limit Diagram (FFLD) of steel TRIP690 to validate the performance of the model. The predicted results are in good agreement with the experimental data over a wide range of stress triaxialities. Comparison between the proposed model and some fracture criteria is also provided, and the results indicate that the proposed model has significant potential to predict ductile fracture as well as FFLD at both low and high triaxialities. In order to validate the capability of the model in structural response, the proposed model has been implemented into user-defined subroutines VUMAT in the finite element program ABAQUS/Explicit. For this purpose, the explicit stress integration algorithms of the model have been explained. The model has been validated by comparing the predicted results with experimental data of steel A533B. The results show the excellent correlation between experiments and simulation for the force and damage results as well as the fracture shape.

本文旨在提出基于连续损伤力学的断裂模型。利用两个屈服面（塑性和损伤）来开发模型。然后提出了一种将应力三轴性和洛德角参数结合在一起的改进延性断裂模型。该模型被用于构造四种类型的金属合金的断裂位点：钢HY100，钢PCrNi3MoVA，铝2024-T351，钢TRIP690和钢A533B。该预测还涉及对HY100和A533B钢的损伤演变对应力三轴性的依赖性进行研究。新模型还用于构造TRIP690钢的断裂极限图（FFLD），以验证模型的性能。预测结果与在广泛的应力三轴性实验数据非常吻合。还提供了所提出的模型与某些断裂标准之间的比较，结果表明所提出的模型在低和高三轴性下都具有预测延性断裂以及FFLD的巨大潜力。为了验证模型在结构响应中的能力，已在有限元程序ABAQUS / Explicit中将提出的模型实现为用户定义的子例程VUMAT。为此，已经解释了模型的显式应力积分算法。通过将预测结果与A533B钢的实验数据进行比较，验证了该模型的有效性。结果表明，力与损伤结果以及断裂形状在实验与模拟之间具有极好的相关性。结果表明，所提出的模型在低和高三轴度下均具有预测延性断裂以及FFLD的巨大潜力。为了验证模型在结构响应中的能力，已在有限元程序ABAQUS / Explicit中将提出的模型实现为用户定义的子例程VUMAT。为此，已经解释了模型的显式应力积分算法。通过将预测结果与A533B钢的实验数据进行比较，验证了该模型的有效性。结果表明，力与损伤结果以及断裂形状在实验与模拟之间具有极好的相关性。结果表明，所提出的模型在低和高三轴度下都具有预测延性断裂以及FFLD的巨大潜力。为了验证该模型在结构响应中的能力，已在有限元程序ABAQUS / Explicit中将提出的模型实现为用户定义的子例程VUMAT。为此，已经解释了模型的显式应力积分算法。通过将预测结果与A533B钢的实验数据进行比较，验证了该模型的有效性。结果表明，力与损伤结果以及断裂形状在实验与模拟之间具有极好的相关性。为了验证该模型在结构响应中的能力，已在有限元程序ABAQUS / Explicit中将提出的模型实现为用户定义的子例程VUMAT。为此，已经解释了模型的显式应力积分算法。通过将预测结果与A533B钢的实验数据进行比较，验证了该模型的有效性。结果表明，力与损伤结果以及断裂形状在实验与模拟之间具有极好的相关性。为了验证模型在结构响应中的能力，已在有限元程序ABAQUS / Explicit中将提出的模型实现为用户定义的子例程VUMAT。为此，已经解释了模型的显式应力积分算法。通过将预测结果与A533B钢的实验数据进行比较，验证了该模型的有效性。结果表明，力与损伤结果以及断裂形状在实验与模拟之间具有极好的相关性。通过将预测结果与A533B钢的实验数据进行比较，验证了该模型的有效性。结果表明，力与损伤结果以及断裂形状在实验与模拟之间具有极好的相关性。通过将预测结果与A533B钢的实验数据进行比较，验证了该模型的有效性。结果表明，力与损伤结果以及断裂形状在实验与模拟之间具有极好的相关性。