Basic Modeling and Theory of Creep of Metallic Materials / / by Rolf Sandström.

• Superior document: Springer Series in Materials Science, 339
• Author: Sandström, Rolf.
• Place / Publishing House: Cham : : Springer Nature Switzerland :, Imprint: Springer,, 2024.
• Year of Publication: 2024
• Edition: 1st ed. 2024.
• Language: English
• Series: Springer Series in Materials Science, 339
• Physical Description: 1 online resource (317 pages)

This open access book features an in-depth exploration of the intricate creep behavior exhibited by metallic materials, with a specific focus on elucidating the underlying mechanical properties governing their response at elevated temperatures, particularly in the context of polycrystalline alloys. Traditional approaches to characterizing mechanical properties have historically relied upon empirical models replete with numerous adjustable parameters, painstakingly tuned to match experimental data. While these methods offer practical simplicity, they often yield outcomes that defy meaningful extrapolation and application to novel systems, invariably necessitating the recalibration of parameters afresh. In stark contrast, this book compiles a compendium of models sourced from the scientific literature, meticulously crafted through ab initio methodologies rooted in fundamental physical principles. Notably, these models stand apart by their conspicuous absence of adjustable parameters. This pioneering effort is envisioned as a groundbreaking initiative, marking the first of its kind in the field. The resulting models, bereft of arbitrary tuning, offer a level of predictability hitherto unattained. Notably, they provide a secure foundation for ascertaining operational mechanisms, contributing significantly to enhancing our understanding of material behavior in high-temperature environments. This open access book is a valuable resource for researchers and seasoned students engaged in the study of creep phenomena in metallic materials. Readers will find a comprehensive exposition of these novel, parameter-free models, facilitating a deeper comprehension of the intricate mechanics governing material deformation at elevated temperatures.

Table of Contents

Intro -- Preface -- Contents -- 1 The Role of Fundamental Modeling -- 1.1 Background -- 1.2 Description -- 1.3 Objectives -- 1.4 Layout -- 1.5 Supplementary Material -- References -- 2 Stationary Creep -- 2.1 The Creep Process -- 2.2 Empirical Models of Secondary Creep -- 2.3 Dislocation Model -- 2.3.1 Work Hardening -- 2.3.2 Dynamic Recovery -- 2.3.3 Static Recovery -- 2.3.4 Accumulated Dislocation Model -- 2.4 The cL Parameter -- 2.5 Secondary Creep Rate -- 2.6 Dislocation Mobility -- 2.6.1 Climb Mobility -- 2.6.2 The Glide Mobility -- 2.6.3 Cross-Slip Mobility -- 2.6.4 The Climb Glide Mobility -- 2.7 Application to Aluminum -- 2.8 Application to Nickel -- 2.9 Summary -- References -- 3 Stress Strain Curves -- 3.1 General -- 3.2 Empirical Methods to Describe Stress Strain Curves -- 3.3 Basic Model -- 3.3.1 The Model -- 3.3.2 Application to Parent Metal -- 3.3.3 Application to Welds -- 3.4 The ω Parameter in Dynamic Recovery -- 3.5 Summary -- References -- 4 Primary Creep -- 4.1 General -- 4.2 Empirical Models for Creep Strain Curves -- 4.3 Dislocation Controlled Primary Creep -- 4.4 Stress Adaptation -- 4.4.1 Model -- 4.4.2 Numerical Integration -- 4.4.3 Applications -- 4.5 12% Cr Steels -- 4.5.1 Dislocation Model -- 4.5.2 Simulated Creep Curves -- 4.6 Summary -- References -- 5 Creep with Low Stress Exponents -- 5.1 General -- 5.2 Model for Diffusional Creep -- 5.3 Grain Boundary Creep -- 5.4 Constrained Grain Boundary Creep -- 5.5 Primary Creep at Low Stresses -- 5.6 Creep at Low Stresses in an Austenitic Stainless Steel -- 5.7 Creep in Aluminium at Very Low Stresses (Harper-Dorn Creep) -- 5.8 Creep in Copper at Low Stresses -- 5.8.1 Creep of Cu-OFP at 600 °C -- 5.8.2 Creep of Copper at 820 °C -- 5.8.3 Creep of Copper at 480 °C -- 5.9 Summary -- References -- 6 Solid Solution Hardening -- 6.1 General -- 6.2 The Classical Picture.

6.2.1 Observations -- 6.2.2 Issues with the Classical Picture -- 6.3 Modeling of Solid Solution Hardening. Slowly Diffusing Elements -- 6.3.1 Lattice and Modulus Misfit -- 6.3.2 Solute Atmospheres -- 6.4 Drag Stress -- 6.5 Modeling of Solid Solution Hardening. Fast Diffusing Elements -- 6.6 Summary -- References -- 7 Precipitation Hardening -- 7.1 General -- 7.2 Previous Models for the Influence of Particles on the Creep Strength -- 7.2.1 Threshold Stress -- 7.2.2 Orowan Model -- 7.2.3 The Role of the Energy Barrier -- 7.3 Precipitation Hardening Based on Time Control -- 7.4 Application of the Precipitation Hardening Model -- 7.4.1 Analyzed Materials -- 7.4.2 Pure Copper -- 7.4.3 Cu-Co Alloys -- 7.5 Summary -- References -- 8 Cells and Subgrains. The Role of Cold Work -- 8.1 General -- 8.2 Modeling of Subgrain Formation -- 8.2.1 The Stress from Dislocations -- 8.2.2 Formation of Subgrains During Creep -- 8.2.3 Cell Formation at Constant Strain Rate -- 8.3 Influence of Cold Work on the Creep Rate -- 8.4 Formation of a Dislocation Back Stress -- 8.5 Summary -- References -- 9 Grain Boundary Sliding -- 9.1 General -- 9.2 Empirical Modeling of GBS During Superplasticity -- 9.3 Grain Boundary Sliding in Copper -- 9.4 Superplasticity -- 9.5 Summary -- References -- 10 Cavitation -- 10.1 General -- 10.2 Empirical Cavity Nucleation and Growth Models -- 10.3 Cavitation in 9% Cr Steels -- 10.4 Basic Model for Cavity Nucleation -- 10.4.1 Thermodynamic Considerations -- 10.4.2 Strain Dependence -- 10.4.3 Comparison to Experiments for Copper -- 10.4.4 Comparison to Experiment for Austenitic Stainless Steels -- 10.5 Models for Cavity Growth -- 10.5.1 Unconstrained Cavity Growth Model -- 10.5.2 Constrained Cavity Growth -- 10.5.3 Strain Controlled Cavity Growth -- 10.5.4 Growth Due to Grain Boundary Sliding -- 10.6 Summary -- References.

11 The Role of Cavitation in Creep-Fatigue Interaction -- 11.1 General -- 11.2 Empirical Principles for Development of Creep-Fatigue Damage -- 11.2.1 Fatigue and Creep Damage -- 11.2.2 Loops During Cyclic Loading -- 11.3 Deformation During Cyclic Loading -- 11.3.1 Basic Model for Hysteresis Loops -- 11.3.2 Application of the Cycling Model -- 11.4 Cavitation -- 11.4.1 Nucleation of Cavities -- 11.4.2 Cavity Growth -- 11.5 Summary -- References -- 12 Tertiary Creep -- 12.1 General -- 12.2 Empirical Models for Tertiary Creep and Continuum Damage Mechanics -- 12.2.1 Models for Tertiary Creep -- 12.2.2 Continuum Damage Mechanics (CDM) -- 12.3 Particle Coarsening -- 12.4 Dislocation Strengthening During Tertiary Creep -- 12.4.1 The Role of Substructure During Tertiary Creep -- 12.4.2 Accelerated Recovery Model -- 12.5 Necking -- 12.5.1 Hart's Criterion -- 12.5.2 Use of Omega Model -- 12.5.3 Basic Dislocation Model -- 12.5.4 Multiaxial Stress States -- 12.6 Summary -- References -- 13 Creep Ductility -- 13.1 Introduction -- 13.2 Empirical Ductility Models -- 13.3 Basic Ductility Methods -- 13.3.1 Brittle Rupture -- 13.3.2 Ductile Rupture -- 13.4 The Role of Multiaxiality -- 13.4.1 Diffusion Controlled Growth -- 13.4.2 Strain Controlled Growth -- 13.4.3 Growth Due to Grain Boundary Sliding (GBS) -- 13.4.4 Comparison of Models -- 13.5 Summary -- References -- 14 Extrapolation -- 14.1 Introduction -- 14.2 Empirical Extrapolation Analysis -- 14.2.1 Basic TTP Analysis -- 14.2.2 The ECCC Post-assessment Tests -- 14.2.3 Use of Neural Network (NN) -- 14.3 Error Analysis in Extrapolation -- 14.3.1 Model for Error Analysis -- 14.3.2 Error Analysis with PATs -- 14.3.3 Error Analysis with NN -- 14.4 Basic Modeling of Creep Rupture Curves -- 14.4.1 General -- 14.4.2 Secondary Creep Rate -- 14.4.3 Creep Strain Curves -- 14.4.4 Cavitation -- 14.4.5 Rupture Criteria.

14.4.6 Extensive Extrapolation of the Creep Rate for Cu -- 14.4.7 Creep Rupture Predictions for Austenitic Stainless Steels -- 14.5 Summary -- Appendix: Derivatives in Neural Network Models (Reproduced from [37] with Permission) -- References.