Dynamic simulation of machining composites using the explicit element-free Galerkin method

Abstract

Machining operations are performed on composite parts to obtain the final geometry. However, machining composites is challenging due to their low machinability and high cost. Numerical modelling of machining presents a valuable tool for cost reduction and a better understanding of the cutting process. Meshfree methods are an attractive choice to model machining problems due to their capability in modelling large deformations. This work presents an explicit meshfree model for orthogonal cutting of unidirectional composites based on the element-free Galerkin (EFG) Method. Advantages of the proposed model include: simple and automated preprocessing, advanced material modelling and ability to model high-speed machining. Workpiece material is modelled as orthotropic Kirchhoff material with a choice of three failure criteria: maximum stress, Hashin and LaRC02. Frictional contact calculations are performed based on central differencing, therefore avoiding the use of penalty parameters. Validation of the EFG model is conducted by comparing cutting forces against orthogonal cutting experiments on GFRP samples using a vertical milling machine. It is found that while the numerical cutting forces are in good agreement with experimental ones, the numerical thrust forces are significantly underestimated. Analysis of failure showed that chip is formed along the fibre direction in the studied range.

Distributions of stress and deformation in a braided wire rope subjected to torsional loading

“…This method is more suitable for solving nonlinear, multi-contact, and large deformation problems. 25,26 Explicit dynamics is widely used in the study of rope structures and is highly efficient in solving multiple contact problems between wires. 14,27,28 Among them, Li et al 28 mentioned that ''In ABAQUS/ Standard, convergence issues should be addressed when the implicit scheme is used.…”

Modeling Grinding Processes—Mesh or Mesh-Free Methods, 2D or 3D Approach?

“…In terms of numerical modeling, new techniques for solving the differential equations describing mechanical and thermal phenomena can be applied to grinding models. Among them, we find the particle finite element method [30,62,63], the material point method [64,65], the element-free Galerking [66], and stabilized optimal transportation mesh-free (OTM) method [67][68][69]. These techniques have been successfully applied to 2D orthogonal cutting simulation; however, the application to 3D simulation of grinding is a field of research to be explored, since there is no available literature, and the numerical methods mentioned are not implemented in commercial software yet.…”

Application of Multisensor Information Fusion Technology in the Measurement of Dynamic Machining Errors of Computer Numerical Control (CNC) Machine Tools

“…In recent years, it has become increasingly common to use multiple sensors of the same type, or multiple sensors of different types, in intelligent systems, and the information collected by the system has become more diverse. However, the effective integration of fused systems composed of multiple sensors into a single system has not been studied enough [5]. Although a lot of research has been done in the past decades to process information from sensor collection systems, the demand for information and the speed of demand are often so great that simply increasing the number of sensors is a solution to meet the system requirements, but this approach results in wasted information and increases the cost of developing intelligent systems [6].…”