Multi-Mode Damage and Fracture Mechanisms of Thin-Walled Tubular Parts with Cross Inner Ribs Manufactured via Flow...

Area of Science:

• Materials Science
• Mechanical Engineering
• Computational Mechanics

Background:

• Thin-walled tubular parts with complex inner ribs are crucial in various industries.
• Understanding multi-mode damage and fracture mechanisms is essential for optimizing manufacturing processes.
• Existing models may not fully capture the intricate failure modes in these components.

Purpose of the Study:

• To modify the Gurson-Tvergaard-Needleman (GTN) model for accurate prediction of damage and fracture in thin-walled tubular parts with cross inner ribs (LTIRs).
• To unify tension and shear damage mechanisms using a novel, asymmetric stress state function.
• To provide insights into fracture behaviors at different zones (non-rib zone, longitudinal rib, rib-interface) under various deformation conditions.

Main Methods:

• Modification of the Gurson-Tvergaard-Needleman (GTN) model by incorporating a new stress state function.
• Unification of tension and shear damage through an asymmetric stress triaxiality function.
• Analysis of fracture mechanisms in non-rib zones, longitudinal ribs, and at the interface between transverse ribs and non-rib zones.

Main Results:

• The modified GTN model successfully predicted fractures in thin-walled tubular parts with LTIRs.
• Fracture modes were identified, including stripping, shear-tension deformation, axial tension effects, and shearing at rib grooves.
• The study detailed the influence of wall thickness reduction and transverse rib interval on fracture behavior.

Conclusions:

• The enhanced GTN model provides a robust framework for predicting multi-mode damage and fracture in complex tubular parts.
• The findings offer critical guidance for the manufacturing of high-performance aluminum alloy thin-walled components with inner ribs.
• This research contributes to improved material performance and manufacturing efficiency in the production of specialized tubular structures.