No abstract

No abstract

No abstract

a b s t r a c tThis paper develops a fast semi-analytical model for solving the three-dimensional elasto-plastic contact problems involving layered materials using the Equivalent Inclusion Method (EIM). The analytical elastic solutions of a half-space subjected to a unit surface pressure and a unit subsurface eigenstrain are employed in this model; the topmost layer is simulated by an equivalent inclusion with fictitious eigenstrain. Accumulative plastic deformation is determined by a procedure involving an iterative plasticity loop and an incremental loading process. Algorithms of the fast Fourier transform (FFT) and the Conjugate Gradient Method (CGM) are utilized to improve the computation efficiency. An analytical elastic solution of layered body contact (O'Sullivan and King, 1988) and an indentation experiment result involving a layered substrate (Michler et al., 1999) are used to examine the accuracy of this model. Comparisons between numerical results from the present model and a commercial FEM software (Abaqus) are also presented. Case studies of a rigid ball loaded against a layered elasto-plastic half-space are conducted to explore the effects of the modulus, yield strength, and thickness of the coating on the hardness, stiffness, and plastic deformation of the composite body.

This paper reports the development of a novel three-dimensional (3D) deterministic model for rough surface line-contact mixed-EHL problems. This model is of great importance because line contacts are found in many mechanical components. The macro aspects of a line-contact problem can be simplified into a two-dimensional (2D) model, but the topography of contacting rough surfaces, micro asperity contacts, and lubricant flows around asperities are often 3D. The present model is based on Hu and Zhu’s unified mixed EHL model [1] and the mixed FFT-based approach formulated by Chen et al [2]. It is numerically verified through comparisons with results from conventional 2D line-contact EHL theories. Numerical examples involving sinusoidal roughness and digitized 3D machined surfaces are analyzed.