PSI - Issue 28

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ScienceDirect

Procedia Structural Integrity 28 (2020) 1018–1023 Structural Integrity Procedia 00 (2020) 000–000 Structural Integrity Procedia 00 (2020) 000–000

www.elsevier.com / locate / procedia www.elsevier.com / locate / procedia

1st Virtual European Conference on Fracture Damage evaluations in Supporting Porous Components using Infrared Thermography and Acoustic Emission and their E ff ects on 1st Virtual European Conference on Fracture Damage evaluations in Supporting Porous Components using Infrared Thermography and Acoustic Emission and their E ff ects on

Loosening Behaviour of Acetabular Cup Yuichi Otsuka a, ∗ , Hiraku Sugawara b , Yukio Miyashita b Loosening Behaviour of Acetabular Cup Yuichi Otsuka a, ∗ , Hiraku Sugawara b , Yukio Miyashita b

a Department of System Safety, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188, Japan. b Department of Mechanical Enginering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188, Japan. a Department of System Safety, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188, Japan. b Department of Mechanical Enginering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188, Japan.

© 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the European Structural Integrity Society (ESIS) ExCo Abstract This study aims at experimentally revealing the e ff ect of accumulated damages in supporting porous components on loosening behaviour using Infrared thermography(IR) and Acoustic emission(AE). Aseptic loosening is occurred due to degradation of fixing force of acetabular cups by biological e ff ects or mechanical loading. However, e ff ects of mechanical loading on loosening behaviors have not been observed yet. An integrated assembly of hip joint components, which is composed of stems and acetabular cups was set in distilled water in order to apply cyclic load in vitro. We developed the simulation system of loosening behaviour of acetabular cups by cyclic loading using cantilever . Damage evaluations on interface between the acetabular cup , HAp coating and supporting porous components ( we call it “ simulated bone ” , which has similar Young ’ s modulus and density for those of cancellous bone) using AE. Additionally inelastic damage behaviour in simulated bone was simultaneously observed using IR. IR could successfully observed dissipation energy by inelastic damage accumulated during cyclic loading, which indicate its fatigue strength within shorter cyclic loading. Cyclic loading test for 1million revealed that both lateral and angular displacement of the acetabular cup can be associated with the progress of damages in delamination of Hap coating or inelastic compression of simulated bone Loosening mechanism of the acetabular cup by cyclic loading can be considered by the contribution of both damages at the interface and in the simulated bone. c ⃝ 2020 The Authors. Published by Elsevier B.V. This is open a cess article under the CC BY- C-ND license (http: // cr ativecomm ns.org / licenses / by-nc-nd / 4.0 / ) Pee under respons bility of the European Structural Integrity Society (ESIS) ExCo. Keywords: Aceptic loosening; Hydroxyapatite coating; Fatigue; Wear; Infrared thermography; Acoustic emission; Interface fracture mechanics Abstract This study aims at experimentally revealing the e ff ect of accumulated damages in supporting porous components on loosening behaviour using Infrared thermography(IR) and Acoustic emission(AE). Aseptic loosening is occurred due to degradation of fixing force of acetabular cups by biological e ff ects or mechanical loading. However, e ff ects of mechanical loading on loosening behaviors have not been observed yet. An integrated assembly of hip joint components, which is composed of stems and acetabular cups was set in distilled water in order to apply cyclic load in vitro. We developed the simulation system of loosening behaviour of acetabular cups by cyclic loading using cantilever . Damage evaluations on interface between the acetabular cup , HAp coating and supporting porous components ( we call it “ simulated bone ” , which has similar Young ’ s modulus and density for those of cancellous bone) using AE. Additionally inelastic damage behaviour in simulated bone was simultaneously observed using IR. IR could successfully observed dissipation energy by inelastic damage accumulated during cyclic loading, which indicate its fatigue strength within shorter cyclic loading. Cyclic loading test for 1million revealed that both lateral and angular displacement of the acetabular cup can be associated with the progress of damages in delamination of Hap coating or inelastic compression of simulated bone Loosening mechanism of the acetabular cup by cyclic loading can be considered by the contribution of both damages at the interface and in the simulated bone. c ⃝ 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of the European Structural Integrity Society (ESIS) ExCo. Keywords: Aceptic loosening; Hydroxyapatite coating; Fatigue; Wear; Infrared thermography; Acoustic emission; Interface fracture mechanics

1. Introduction 1. Introduction

The number of patients su ff ering from gonarthrosis and other diseases of the joint and artificial hip joint replace ment surgery has been increasing in superaging society. Artificial hip joints consist of a stem, an artificial head, liner and acetabular cups[1]. Loosening in the acetabular components is the most common cause of revision in the artificial The number of patients su ff ering from gonarthrosis and other diseases of the joint and artificial hip joint replace ment surgery has been increasing in superaging society. Artificial hip joints consist of a stem, an artificial head, liner and acetabular cups[1]. Loosening in the acetabular components is the most common cause of revision in the artificial

2452-3216 © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the European Structural Integrity Society (ESIS) ExCo 10.1016/j.prostr.2020.11.117 ∗ Corresponding author. Tel.: + 81-258-47-9575. E-mail address: otsuka@vos.nagaokaut.ac.jp 2210-7843 c ⃝ 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of the European Structural Integrity Society (ESIS) ExCo. ∗ Corresponding author. Tel.: + 81-258-47-9575. E-mail address: otsuka@vos.nagaokaut.ac.jp 2210-7843 c ⃝ 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of the European Structural Integrity Society (ESIS) ExCo.