Smooth particle hydrodynamics simulation of damage induced by a spherical indenter scratching a viscoplastic material

Abstract

We present an implementation of a (mesh-free) smooth particle hydrodynamics (SPH) algorithm, intended for the application to solid bodies, and use it to simulate scratch-induced surface damage on an elasto-viscoplastic material. If conventional SPH is used to simulate solids, an unphysically high artificial viscosity is required to damp strong oscillatory modes and thus stabilize the system. To overcome these intrinsic difficulties associated with modeling solid bodies, the recently implemented so-called total-Lagrangian SPH utilizes an hourglass control scheme similar to what is known from finite element algorithms. Elasto-viscoplastic material properties are modeled by using the Mie–Grüneisen equation of state and the Johnson–Cook model. The material parameters are selected to reproduce the strain-stress behavior of annealed oxygen-free high conductivity copper. The spherical indenter is modeled as a rigid sphere. The topographies of the calculated scratch-induced surface damage are in excellent agreement with experimental scratch tests carried out at comparable normal loads. We also calculate the real contact area between the indenter and the surface, allowing a sound estimation of the scratch hardness

Microstructural changes and strain hardening effects in abrasive contacts at different relative velocities and temperatures

“…E.g. phase texture change, orientation and misorientation due to deformation, grain and sub-grain boundary formation can be detected [36].…”

A new total‐Lagrangian smooth particle hydrodynamics approximation for the simulation of damage and fracture of ductile materials

“…The use of this solution has not been widely adopted by the SPH community, probably due to the increase in the required computational effort and also the insufficient knowledge about where to located the stress points at the expense of computation time . To control instabilities arising from rank deficiency, Ganzenmüller proposed a control algorithm that was shown to be very effective . In what follows, we detail in the absence of damage the TLSPH approximation, the set of expressions used to describe the deformation of a solid body, and the hourglass control.…”

“…Recent extensions now allow SPH to be used to simulate solid mechanics problems . The natural abilities of SPH to simulate problems involving large deformations make it gain popularity in the modeling of solids in the fields of machining, wear, and resistance to impacts . Indeed, for the simulation of these kinds of problems, true meshfree particle methods, such as SPH, have the advantage over mesh‐based methods such as finite‐element method (FEM) of not requiring a mesh, thus avoiding potentially problematic remeshing when large distortions occur.…”

“…This makes TLSPH attractive for the simulation of solids experiencing large deformations coupled with damage. Indeed, TLSPH is being increasingly used to simulate the mechanical response of a ductile material to scratches, impacts, or machining …”

Development and validation of a meshless 3D material point method for simulating the micro-milling process

“…To determine the deviatoric part of the stress tensor in Eq. (26), the purely empirical Johnson-Cook model by Johnson and Cook (1985) is used, which is numerically robust and therefore widely used for thermal elastic-plastic modeling, where the calculation of σ d is illustrated in Leroch et al (2016). The relation for the flow stress σ f is given as…”