Cutting modeling using cohesive zone concept of titanium/CFRP composite stacks

Abstract

In modern aerospace industry, hybrid CFRP/Ti stacks have taken a prominent position in manufacturing aircraft and spacecraft structural components due to their combined resistance and enhanced characteristics favoring the energy saving. Compared to the great interest of experimental studies, nearly rare scientific literature deals with the numerical modeling of hybrid CFRP/Ti cutting. This is the key incentive that motivates the current research to propose an original FE model to address the mentioned issues. The FE model was developed into Abaqus/Explicit commercial code. The CFRP phase was modeled as an equivalent homogeneous material (EHM) by implementing Hashin damage criteria to simulate the rupture and separation of the fiber/matrix system. The Ti phase was assumed isotropic with elastoplastic behavior, and Johnson-Cook criteria were utilized to replicate the local failure of the metallic phase. The CFRP/Ti interface physically described as an intermediate constituent was modeled through the concept of cohesive zone (CZ). The multiple aspects of machining responses induced in hybrid CFRP/Ti cutting were precisely investigated with a special focus on the interface damage formation. The numerical results highlighted the significant effects of feed rate on the force generation and the pivotal role of bi-material interface consumption (BIC) in affecting the interface delamination.