Fatigue reliability evaluation of aluminium alloy coated with Diamond-Like Carbon/AlN hybrid coatings by UBMS

In our previous study, it was found that the wear life of the DLC/AlN hybrid film compared with a DLC film deposited directly onto Al-alloy could be improved by controlling the hardness of the AlN intermediate layer film. However, the hard coating like above films has a possibility to decline the fa...

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Main Authors: Masashi NAKAMURA, Yuki TAKAMORI
Format: Article
Language:Japanese
Published: The Japan Society of Mechanical Engineers 2016-08-01
Series:Nihon Kikai Gakkai ronbunshu
Subjects:
Online Access:https://www.jstage.jst.go.jp/article/transjsme/82/840/82_16-00157/_pdf/-char/en
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author Masashi NAKAMURA
Yuki TAKAMORI
author_facet Masashi NAKAMURA
Yuki TAKAMORI
author_sort Masashi NAKAMURA
collection DOAJ
description In our previous study, it was found that the wear life of the DLC/AlN hybrid film compared with a DLC film deposited directly onto Al-alloy could be improved by controlling the hardness of the AlN intermediate layer film. However, the hard coating like above films has a possibility to decline the fatigue strength of based material. In the present study, to ensure the fatigue reliability of Al alloy coated with DLC/AlN hardness gradient hybrid film, the fatigue strength and the fatigue failure mechanism were investigated. Fatigue strength of A7075 alloy coated with DLC/AlN hybrid film in lower stress side was higher than the untreated material, but that in higher stress side was almost the same as the untreated material. Compressive residual stress of A7075 alloy coated with DLC/AlN composite film was larger than the untreated material. From the observation of crack initiation part in the fracture surface of the A7075 alloy coated with DLC/AlN hybrid film by SEM, micro cracks in AlN film were found to be generate from the interface between Al base material and AlN film by the local plastic deformation in Al base material. Since the DLC film with a high fracture toughness values obstruct that micro cracks came out to the film surface, the initiation of a main crack was delay. As the result, the fatigue life of DLC/AlN hybrid coating material was improved. DLC/AlN hybrid coating is considered to represent a simple and effective means of improving the wear resistance and fatigue reliability of Al-alloy components commonly used within the aerospace and automotive industries.
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spelling doaj.art-5c0957197ceb4cd8b65f6db3e1dee7312022-12-22T02:47:25ZjpnThe Japan Society of Mechanical EngineersNihon Kikai Gakkai ronbunshu2187-97612016-08-018284016-0015716-0015710.1299/transjsme.16-00157transjsmeFatigue reliability evaluation of aluminium alloy coated with Diamond-Like Carbon/AlN hybrid coatings by UBMSMasashi NAKAMURA0Yuki TAKAMORI1Department of Intelligence System Engineering, College of Engineering, Ibaraki UniversityGraduate School of Intelligence System Engineering, Ibaraki UniversityIn our previous study, it was found that the wear life of the DLC/AlN hybrid film compared with a DLC film deposited directly onto Al-alloy could be improved by controlling the hardness of the AlN intermediate layer film. However, the hard coating like above films has a possibility to decline the fatigue strength of based material. In the present study, to ensure the fatigue reliability of Al alloy coated with DLC/AlN hardness gradient hybrid film, the fatigue strength and the fatigue failure mechanism were investigated. Fatigue strength of A7075 alloy coated with DLC/AlN hybrid film in lower stress side was higher than the untreated material, but that in higher stress side was almost the same as the untreated material. Compressive residual stress of A7075 alloy coated with DLC/AlN composite film was larger than the untreated material. From the observation of crack initiation part in the fracture surface of the A7075 alloy coated with DLC/AlN hybrid film by SEM, micro cracks in AlN film were found to be generate from the interface between Al base material and AlN film by the local plastic deformation in Al base material. Since the DLC film with a high fracture toughness values obstruct that micro cracks came out to the film surface, the initiation of a main crack was delay. As the result, the fatigue life of DLC/AlN hybrid coating material was improved. DLC/AlN hybrid coating is considered to represent a simple and effective means of improving the wear resistance and fatigue reliability of Al-alloy components commonly used within the aerospace and automotive industries.https://www.jstage.jst.go.jp/article/transjsme/82/840/82_16-00157/_pdf/-char/enfatigue reliabilitysufface modifficationthin filmdlcalnredidual stressfracture toughness
spellingShingle Masashi NAKAMURA
Yuki TAKAMORI
Fatigue reliability evaluation of aluminium alloy coated with Diamond-Like Carbon/AlN hybrid coatings by UBMS
Nihon Kikai Gakkai ronbunshu
fatigue reliability
sufface modiffication
thin film
dlc
aln
redidual stress
fracture toughness
title Fatigue reliability evaluation of aluminium alloy coated with Diamond-Like Carbon/AlN hybrid coatings by UBMS
title_full Fatigue reliability evaluation of aluminium alloy coated with Diamond-Like Carbon/AlN hybrid coatings by UBMS
title_fullStr Fatigue reliability evaluation of aluminium alloy coated with Diamond-Like Carbon/AlN hybrid coatings by UBMS
title_full_unstemmed Fatigue reliability evaluation of aluminium alloy coated with Diamond-Like Carbon/AlN hybrid coatings by UBMS
title_short Fatigue reliability evaluation of aluminium alloy coated with Diamond-Like Carbon/AlN hybrid coatings by UBMS
title_sort fatigue reliability evaluation of aluminium alloy coated with diamond like carbon aln hybrid coatings by ubms
topic fatigue reliability
sufface modiffication
thin film
dlc
aln
redidual stress
fracture toughness
url https://www.jstage.jst.go.jp/article/transjsme/82/840/82_16-00157/_pdf/-char/en
work_keys_str_mv AT masashinakamura fatiguereliabilityevaluationofaluminiumalloycoatedwithdiamondlikecarbonalnhybridcoatingsbyubms
AT yukitakamori fatiguereliabilityevaluationofaluminiumalloycoatedwithdiamondlikecarbonalnhybridcoatingsbyubms