In the present investigation, creep–fatigue interaction was studied in an alpha–beta titanium alloy Ti-6Al-4V at ambient temperature. Stress controlled low cycle fatigue tests were conducted with and without hold times. The hold times were introduced to simulate creep phenomenon. The creep damage was found to be responsible for a large reduction in life of the sample tested with hold time. © 2015, The Indian Institute of Metals - IIM.

S. Ganesh Sundara Raman

Department of Metallurgical and Materials Engineering

Jalaj Kumar

Vikas Kumar

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Transactions of the Indian Institute of Metals

Aeroengine titanium alloys such as Ti-6Al-4V experience creep-fatigue loading conditions during the critical fighter aircraft operations. To ensure and enhance the reliable application of such alloys, mechanical behaviour across multiple length scales need renewed attention. Hence, in the present investigation, an attempt has been made to study creep-fatigue damage across multiple length scales (microstructure to component level) using damage mechanics methodology for Ti-6Al-4V alloy. This involves ambient creep, fatigue and creep-fatigue experimentation; identification of various parameters for creep and fatigue models; developing a creep-fatigue model and finally application of this model for damage simulation at specimen, component and microstructure levels. At specimen level, creep-fatigue damage has been obtained from simulations and compared with experimental values. A very good comparison has been observed for the applied maximum peak stress range of 925–975 MPa. The creep-fatigue model has also been successful in mapping damage and identifying critical damage locations in component as well as in the microstructure. © 2018 Elsevier Ltd

International Journal of Fatigue

Creep-fatigue damage simulation at multiple length scales for an aeroengine titanium alloy

This study investigates the mechanistic approach to evaluate total stored energy consisting of damage energy (due to voids and microcracks) and deformation energy (due to dislocations). Thermal data obtained by online IRT technique have been employed for this evaluation. The deformation energy is estimated through EBSD analysis. Subsequently, the damage and deformation induced by creep and fatigue have been modeled as functions of applied stress and cumulative plastic strain, individually. By using the data of experimental creep stress and fatigue strain for each creep-fatigue cycle, the contributions of creep and fatigue damage energies have been estimated for creep-fatigue interaction. New fatigue and creep damage parameters have been proposed based on the damage mechanics concepts. Different regimes have been identified and explained with creep and fatigue damage evolution curves. The present approach has also been extended to characterize incremental creep-fatigue interactions. © 2017 Elsevier Ltd

Creep-fatigue damage modeling in Ti-6Al-4V alloy: A mechanistic approach

In the present investigation, microtexture analysis using electron back-scattered diffraction technique has been performed to study fatigue- and creep-fatigue damages and associated deformation structures in Ti-6Al-4V alloy. Special emphasis has been given to low-angle grain boundary configuration and its possible application as a damage indicator. Damage is mostly present in the form of voids as investigated through scanning electron microscopy. Stored deformation energies have been evaluated for the strain-controlled fatigue-, the stress-controlled fatigue-, and the creep-fatigue-tested samples. Stored deformation energies have also been analyzed vis-à-vis total damage energies to quantify the contribution of damages to various samples. A relation between the stored deformation energy and the applied strain amplitude has been proposed in this study. © 2016, The Minerals, Metals &amp; Materials Society and ASM International.

Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science

Microtexture Analysis and Modeling of Ambient Fatigue and Creep-Fatigue Damages in Ti-6Al-4V Alloy

IOP Conference Series: Materials Science and Engineering

Grain boundary sliding induced by lattice dislocation activity during ambient temperature creep in h.c.p. metals

MATERIALS TRANSACTIONS

Intragranular Deformation Mechanisms during Ambient-Temperature Creep in Hexagonal Close-Packed Metals

Scripta Materialia

Distinguishing the ambient-temperature creep region in a deformation mechanism map of annealed CP-Ti

Acta Materialia

Phenomenological and microstructural analysis of room temperature creep in titanium alloys

Low cycle fatigue—dwell effects and damage mechanisms1This paper is dedicated to Dr Gary R. Halford for all the support, guidance, and mentoring he provided.1

Creep–Fatigue Interactions in Ti-6Al-4V Alloy at Ambient Temperature

Journal	Data powered by TypesetTransactions of the Indian Institute of Metals
Publisher	Data powered by TypesetSpringer India
ISSN	09722815
Open Access	No