Identification of damage parameters for Ti‐6Al‐4V titanium alloy using continuum damage mechanics

Abstract

Modelling ductile damage is one of the most important applications of continuum damage mechanics (CDM) models. Scientists have previously tried to identify the damage parameters and have calibrated the failure behaviour of different materials using CDM models. However, more comprehensive studies are still needed to investigate the capabilities of CDM models for different materials. It is possible to extend the methodology to titanium alloys that are, currently, an optimal solution for highly stressed mechanical components. Therefore Lemaitre's CDM model parameters for ti-6Al-4V titanium alloy have been identified and reported in this work. A series of experimental tests have been carried out to identify the CDM model's parameters by the method of degradation of elastic modulus. A subroutine has been written in ABA-QUS to numerically simulate the behaviour of the simple specimen using Lemaitre's model. Keywords: Continuum damage mechanics / Ti-6Al-4V titanium alloy / ductile damage / numerical simulation / Die Modellierung duktiler Schädigung ist eine der wichtigsten Anwendungen der Kontinuums-Schädigungsmechanik (CDM). Forscher haben versucht die Schädigungsparameter verschiedener Materialien durch CDM zu identifizieren und somit die Versagensverhalten zu kalibrieren. Um die Fähigkeit von CDM in verschiedenen Materialien zu untersuchen, sind jedoch umfassende Studien erförderlich. Es ist möglich, diese Methode auch auf Titanlegierungen zu erstrecken, die sich heutzutage als eine optimale Lösung für anspruchsvolle mechanische Komponenten anbieten. Deshalb werden in dieser Arbeit auch die Lemaitre CDM-Parameter identifiziert und präsentiert. Um die CDM-Parameter (durch die Bestimmung der Abnahme des Elastizitätmodul) zu identifizieren, wurden eine Reihe von experimentellen Untersuchungen durchgeführt. Um das Verhalten durch ein einfaches Modell (Lemaitre) zu simulieren, wurde eine Unterprogramm in Abaqus geschrieben.

A Probabilistic Design Method for Fatigue Life of Metallic Component

“…These plots were obtained by sampling the parameters from given distributions and computing the model output at each sample. The initial distributions of parameters are assumed to be uniform and in the range of reported values for Ti6Al4V material in the literature [18,25,[43][44][45][46] and are presented in Table 1.…”

A Probabilistic Design Method for Fatigue Life of Metallic Component

“…These plots were obtained by sampling the parameters from given distributions and computing the model output at each sample. The initial distributions of parameters are assumed to be uniform and in the range of reported values for Ti6Al4V material in the literature [1,27,13,46,48,23] and are presented in Table 1.…”

Geometry Transferability of Lemaitre's Continuum Damage Mechanics Model in the Plane Stress Specimens

“…Inverse engineering try and error method has been used for the identification of the model parameters with an optimization software called Ls-opt (for the data from smooth specimen). A CDM model has been calibrated by authors for the simple cubic specimens [12]. These calibrated values for the model parameters have been used as initial values in the try and error process.…”

“…In this paper ti-6AL-4V titanium alloy has been chosen as test material. Ti-6Al-4V is a commonly used material in the aerospace industries and was also previously investigated by the same authors [12]. In this paper, four types of different plane stress flat specimens are designed and experimental tests have been done on them.…”