Wear In Advanced Engineering Applications And Materials

Description

Wear is one of the main reasons mechanical components and materials become inoperable, rendering enormous costs to society over time. Estimating wear allows engineers to predict the useful life of modern mechanical elements, reduce the costs of inoperability, or obtain optimal designs (i.e. selecting proper materials, shapes, and surface finishing according to mechanical conditions and durability) to reduce the impact of wear. Wear in Advanced Engineering Applications and Materials presents recent computational and practical research studying damage and wear in advanced engineering applications and materials. As such, this book covers numerical formulations based on the finite element method (FEM) — and the boundary element method (BEM) — as well as theoretical and experimental research to predict the wear response or life-limiting failure of engineering applications. Contents Preface About the Editors Chapter 1. Fretting Fatigue and Wear of Spline Couplings: From Laboratory Testing to Industrial Application through Computational Modelling 1. Introduction 2. Industrial Application 3. Design for Fretting 3.1. Fretting maps 3.2. Analytical methods 4. Laboratory-Scale Testing of Spline Coupling 5. Computational Modelling of Fretting in Splines 5.1. 3D FE model of spline coupling frictional contact 5.2. Modelling wear in spline coupling 5.3. Prediction of fretting fatigue in spline coupling with wear 6. Representative Test Specimen Concept for Fretting in Splines 7. Simple Parameters for Prediction of Fretting 8. Conclusions Acknowledgements References Chapter 2. Fretting Fatigue Life Assessment by Accounting Wear 1. Introduction 2. Wear Modelling 3. Multiaxial Fatigue Models 3.1. Smith–Watson–Topper 3.2. Modified W¨ohler curve method 3.3. Findley model 3.4. Definition of the shear stress amplitude 4. Theory of Critical Distances 5. Wear Assessment for Partial Slip Fretting Fatigue 5.1. Fretting fatigue data 5.2. Assessment of fretting fatigue lives: Partial slip regime 6. Assessment of Fretting Fatigue Lives — Gross Sliding Regime 7. Final Remarks References Chapter 3. Numerical Frameworks for the Wear Modelling of Key Engineering Materials 1. Introduction 1.1. Wear formulations 1.2. Wear modelling 2. Comparative Examples 2.1. General settings 2.2. Rotational abrasion 2.3. Reciprocate sliding 2.4. Fretting 3. Final Remarks References Chapter 4. Wear in Heavily-Loaded Lubricated Contacts 1. Introduction 1.1. Wear mechanisms in EHL contacts 2. Mixed-Lubrication Modelling 2.1. Dry contact solver 2.1.1. Algorithm 2.2. Lubricated contact solver 2.2.1. Particular integral 2.2.2. Complementary function 2.2.3. Applicability limits 2.3. The combined model 3. Mild Wear Model for EHL Contacts 4. Example: Wear Calculation of Two EHL Surfaces with Relative Motion 5. Wear-Fatigue Interaction in Contact Profiles 5. Wear-Fatigue Interaction in Contact Profiles 6. Conclusions Nomenclature References Chapter 5. In-silico Analytical Wear Predictions: Application to Joint Prostheses 1. Introduction 2. Wear Modelling: Overview 3. Wear Law 3.1. Unilateral or bilateral wear 3.2. Local formulation of Archard’s wear law 3.3. Experimental evaluation of the wear coefficient/law 3.4. Anisotropic wear: Cross-shear phenomenon 4. Prediction of Wear in Artificial Joints 4.1. Hip and shoulder implants 4.2. Models description 4.2.1. Model assumptions 4.2.2. Wear laws/model 4.2.3. Input data 4.2.4. Model implementation 4.2.4.1. Contact analysis 4.2.4.2. Kinematic analysis 4.2.4.3. Wear assessments 4.3. Wear simulations of MoP HA 4.3.1. Effect of wear laws 4.3.2. Effect of BCs 4.4. Wear simulations of MoM HA 4.4.1. Effect of friction 4.4.2. Estimation of distinct wear coefficients for head and cup 4.5. Wear simulations of MoP RTSA 4.5.1. Estimation of specific wear coefficients for RTSA 4.5.2. Effect of size and dimensional tolerance on wear 4.6. Wear law/model validity 5. Conclusions References Chapter 6. In-silico Finite Element Wear Predictions 1. Introduction 2. FE Wear Models: General Aspects 2.1. Wear calculation 2.1.1. Implicit or explicit kinematics 2.1.2. Unilateral wear or bilateral wear 2.2. Mesh definition 2.3. Model validation 3. Simulation of Cyclic Conditions 3.1. General procedure 3.2. Application to cylinder-on-plate reciprocating wear tests 3.2.1. Model description 3.2.2. Results 3.2.2.1. Model convergence analysis 3.2.2.2. Evolution of contact and wear parameters 3.2.2.3. Effect of the wear partition factor 3.2.2.4. Effect of the stroke amplitude 4. Application of the Submodelling Technique 4.1. General aspects and procedure description 4.2. Validation of the submodelling procedure 4.2.1. Models’ description 4.2.2. Results 4.2.2.1. Convergence analysis of the global model 4.2.2.2. Definition of the cut boundaries 4.2.2.3. Definition of the boundary conditions 4.2.2.4. Convergence analysis of the local model 4.2.2.5. Wear results and procedure validation 5. Conclusions References Chapter 7. Modelling Wear Using the Finite Element Method in Abaqus 1. Introduction 2. General Procedure 3. Friction Models 3.1. Basic Coulomb friction model 3.1.1. Applying the basic friction model 3.1.2. Defining static and kinetic friction coefficients using the basic friction model 3.1.3. Defining static and kinetic friction coefficients using exponential decay 3.1.4. Defining a shear stress limit 3.1.5. Applying anisotropic friction 4. Adaptive Meshing 4.1. Defining an adaptive mesh domain 4.2. Defining adaptive mesh constraints 4.3. Defining adaptive mesh controls 5. Defining the Ablation Equation 5.1. UMESHMOTION structure 5.1.1. UMESHMOTION variables 5.1.2. Utility routines 5.2. Example 1: Wiring a UMESHMOTION subroutine to simulate the wear of material as a function of the contact pressure 6. Creating a Wear Simulation 6.1. Example 2: Creating a functional model to simulate wear based on the Holm–Archard equation 6.1.1. Geometry and FE-mesh 6.1.2. Loads, boundary conditions and contact interactions 6.1.3. Adaptive mesh domain and constraints 6.1.4. Mesh motion (ablation equation) 6.1.5. Reading and understanding the results 7. Practical Considerations 7.1. Defining the mesh motion velocity (wear coefficient) 7.2. Accelerating wear 8. Concluding Remarks References Chapter 8. Wear Modelling in Fibre-Reinforced Composite Materials 1. Introduction 2. Governing Equations 2.1. Unilateral contact law 2.2. Frictional contact laws for FRP 2.3. Wear law for FRP 3. Numerical approximation 3.1. Boundary element equations 3.2. Contact discrete equations 3.3. Solution algorithm 4. Numerical examples 4.1. Thick and thin films indentation response 4.2. Thick and thin films under fretting wear conditions 5. Concluding Remarks References Index