The effect of orthotropic material gradation on the plane sliding frictional contact mechanics problem

Abstract

With the advent of new functional and intelligent non-conventional materials, understanding the behavior of these materials in different contact conditions over the conventional materials is one of the most crucial aspects in early design process for coated systems. Therefore, the sliding contact problem for a functionally graded orthotropic coating–substrate system and a rigid cylindrical punch is considered in this article to study the aforementioned aspects. The functionally graded orthotropic coating is modeled to be bonded to an isotropic substrate of finite thickness and is loaded by a sliding rigid cylindrical punch under plane strain conditions. For the material orthotropy, five different real orthotropic materials are utilized and the stiffness coefficients of each principal direction are graded separately. Navier’s equations are converted to ordinary differential equations using the Fourier integral transformation technique. Then, the algebraic equations are solved and the problem is cast into a singular integral equation. A parametric finite element analysis based on augmented contact method is also conducted. The normalized surface stress distributions and the normalized contact boundaries obtained from finite element analysis are validated with the results obtained from singular integral equation approach. The results of this study may be helpful for engineers in design and optimization of the characteristics of non-conventional coatings that are used as thermal or structural barriers and wear-resistant surfaces in engineering applications.

Dynamic analysis of an exponentially graded viscoelastic coated half plane pressed by a rigid flat punch

“…Frictional and frictionless plane strain contact problems of an FG coated isotropic half plane are studied by Guler and Erdogan (2007), Ke and Wang (2007), Choi and Paulino (2008) and Attia and El-Shafei (2019). Sliding plane strain contact problem of a laterally graded FG orthotropic half plane (Arslan, 2017), an FG orthotropic coated half plane (Alinia et al, 2018) and an FG orthotropic coated isotropic layer (Yilmaz et al, 2019) are examined using Fourier integral transform technique when the system is pressed by the rigid flat or cylindrical punches. Axisymmetric contact problems of an FG half plane or FG coated half plane are investigated by Giannakopoulos and Suresh (1997) Among contact problems, the moving contact problem, in which the motion of the punch at constant velocity is analyzed, has an important place.…”