{"created":"2023-06-19T10:29:42.757466+00:00","id":9692,"links":{},"metadata":{"_buckets":{"deposit":"6a8bb852-616e-42d3-8782-104ffd3ae29f"},"_deposit":{"created_by":18,"id":"9692","owners":[18],"pid":{"revision_id":0,"type":"depid","value":"9692"},"status":"published"},"_oai":{"id":"oai:muroran-it.repo.nii.ac.jp:00009692","sets":["41:227"]},"author_link":["55194"],"item_81_date_granted_17":{"attribute_name":"学位授与年月日","attribute_value_mlt":[{"subitem_dategranted":"2018-03-23"}]},"item_81_degree_grantor_10":{"attribute_name":"学位授与機関","attribute_value_mlt":[{"subitem_degreegrantor":[{"subitem_degreegrantor_language":"ja","subitem_degreegrantor_name":"室蘭工業大学"},{"subitem_degreegrantor_language":"en","subitem_degreegrantor_name":"Muroran Institute of Technology"}],"subitem_degreegrantor_identifier":[{"subitem_degreegrantor_identifier_name":"10103","subitem_degreegrantor_identifier_scheme":"kakenhi"}]}]},"item_81_degree_name_11":{"attribute_name":"学位名","attribute_value_mlt":[{"subitem_degreename":"博士（工学）","subitem_degreename_language":"ja"}]},"item_81_description_25":{"attribute_name":"フォーマット","attribute_value_mlt":[{"subitem_description":"application/pdf","subitem_description_type":"Other"}]},"item_81_description_7":{"attribute_name":"抄録","attribute_value_mlt":[{"subitem_description":"将来の環境・エネルギーシステムにおいて、構造材料にセラミック複合材料を利用することは、金属材料を用いた場合に比べてシステムを高温で運用することを可能となるため、エネルギー効率という点で極めて魅力的である。セラミック材料は本質的に靱性に乏しく、構造材料に用いるためには強化材を用いた複合化によって靱性を確保する必要がある。粒子強化、短繊維強化といった強化法と比較して、長繊維強化は靱性の大きく向上するため構造材料として利用に適している。一方で長繊維強化は長繊維の配向により強度異方性が生じる。セラミック複合材料は成形後の形状付与や追加工が困難であり、部材の最終形状に極めて近い形状で成型する「ニアネット成形」が行われるのが一般的である。複雑形状のニアネット成形のよる部材製作では、複雑に配置された長繊維の間に強固なセラミックマトリックスを形成させるために、部材の形状に応じた成型法と成型条件の選定が必要となる。そのため同じ材質のセラミック複合材料であっても、形状が異なれば性質が異なる。例えば平板形状の機械特性評価結果は、他の形状の同じ材質の部材の特性に直接的には適用できず、形状に応じた機械特性評価法開発が必要となる。環境・エネルギーシステムにおいては、冷却媒体などが流れる冷却管や、耐圧構造で必要とされる円管形状部材の評価法が特に必要とされている。金属材料の円管形状部材の評価法研究は数多くあるが、延性の乏しいセラミック複合材料での応用例は少なく基礎からの評価法研究が必要である。本研究では円管形状のセラミック複合材料の機械特性評価法について研究を行い、特にフープ応力に関わる情報を得ることを目的とする。本論文は全8章で構成されている。第1章の序論を述べ、第2章において背景と研究の位置づけの詳細を示している。第3章は円管試験片に差し込んだ、円管内径と形状を合せた二本のキーを上下に引張り円管試験片を変形させる円周方向引張試験法の検討を行った。金属材料とは異なり、硬いセラミック複合材料においては、キーと円管内径の微妙な形状の違いから、点もしくは線接触により応力が部材に付与されて変形が進行し、キーと試験片が密着する前に破壊に至ることを見出した。フープ応力は円環壁内の円周方向の引張応力であるが、円周方向引張試験においては、キーにより引っ張られている円管試験片の両側面および上下面には曲げモーメントが生じており、試験片は曲げ試験を行っている状態に近くなっていて最弱部が破壊する。円管に引張応力のかかる条件を有限要素解析により解析し、キーを線接触とする形状と接触位置の調整により両側側面部の厚さ方向に全体にある程度均一な分布の引張応力が得られることを見出した。第4章は円周方向引張試験時の破壊領域別応力状態の解明を行い、第5章は変形部位を側面に限定するための並行部・ノッチ形状の検討を行っている。第6章は他の機械試験法、内圧試験法との相関関係の議論を行って、以上をまとめて最終章で論文の総括を行っている。形状に関わらずほぼ同等の素材として扱うことが可能な金属材料と異なり、セラミック複合材料は最終成型品の形状毎に強化繊維構造や製造技術が変化する点を問題意識として議論を行っており、円管形状部材に関しての長繊維強化セラミック複合材料の機械特性評価技術の確立に寄与する研究である。","subitem_description_language":"ja","subitem_description_type":"Abstract"},{"subitem_description":"This thesis studies about the mechanical property investigation method for the ceramic composites having cylindrical shapes. Long fiber reinforced ceramic composites are usually produced by a “near-net shaping” method which is the method to produce a composite having very closed shape to the final shape of the product. The long fiber reinforcements are arranged in the near-net shaped composite to apply an appropriate mechanical property to the composite. The composite tends to have anisotropy of mechanical properties depending on the fiber architectures. For the production of the complex shaped composite, an appropriate production method needs to be chosen. This thesis focuses on the mechanical property investigation for cylindrical shaped ceramic composites such as tubes and cylinder which are used as pressure vessels, cooling tubes and fuel pins of fission reactors. The chapter 1 is an introduction, where importance of ceramic composites toward continuous growth of sustainable society on earth, is emphasized. Then background and objective of this study are explained. The chapter 2 presents several mechanical investigation methods for cylindrical components. Especially the importance of hoop strength investigation is emphasized. The chapter 3 cares the developments and analysis of a circumferential tensile test method. In the case of metal, the surface of keys fit to the inner surface of the cylindrical specimen and resulting in applying tensile stress to the both side of the specimens. In the case of the ceramic composites, because of the small deformation tolerance, the keys contacted to the inner surface of cylindrical specimens by line contacts. Bending stress and moments applied to the cylindrical specimen and the specimen was broken at the weakest point. For the investigation of hoop strength, the application of tensile stress to the inner surface of the cylindrical specimen was expected to be important, and the finite element method revealed that the tensile stress would be able to be applied to the both side of a cylindrical specimen by the adjustment of contact points of keys and the specimen. The chapter 4 cares the failure location during the circumferential tensile test. The chapter 5 cares the notch effects for the circumferential tensile test results. The deformation behavior of a cylindrical specimen having several type notches were characterized using strain gages and discussed the fracture behavior of the specimens. The chapter 6 provides comparison of the circumferential tensile test with the other tests including hydrostatic pressure and expanded plug tests. The chapter 7 is summary of this thesis, emphasize that the different shaped ceramic composites need their own evaluation methods, and the quasi-tensile condition is able to be formed at the both side of a cylindrical specimen by appropriate notch formation and adjustment of the key shapes. A feasibility of the circumferential tensile test method to receive data relating to the hoop strength of the ceramic composites is represented in this research.","subitem_description_language":"en","subitem_description_type":"Abstract"}]},"item_81_dissertation_number_13":{"attribute_name":"学位授与番号","attribute_value_mlt":[{"subitem_dissertationnumber":"甲第423号"}]},"item_81_identifier_registration":{"attribute_name":"ID登録","attribute_value_mlt":[{"subitem_identifier_reg_text":"10.15118/00009644","subitem_identifier_reg_type":"JaLC"}]},"item_81_subject_9":{"attribute_name":"日本十進分類法","attribute_value_mlt":[{"subitem_subject":"501","subitem_subject_scheme":"NDC"}]},"item_81_text_12":{"attribute_name":"学位の種別","attribute_value_mlt":[{"subitem_text_language":"ja","subitem_text_value":"課程博士"}]},"item_81_text_14":{"attribute_name":"報告番号","attribute_value_mlt":[{"subitem_text_language":"ja","subitem_text_value":"甲第423号"}]},"item_81_text_15":{"attribute_name":"学位記番号","attribute_value_mlt":[{"subitem_text_language":"ja","subitem_text_value":"博甲第423号"}]},"item_81_text_16":{"attribute_name":"研究科・専攻","attribute_value_mlt":[{"subitem_text_language":"ja","subitem_text_value":"工学専攻"}]},"item_81_version_type_24":{"attribute_name":"著者版フラグ","attribute_value_mlt":[{"subitem_version_resource":"http://purl.org/coar/version/c_970fb48d4fbd8a85","subitem_version_type":"VoR"}]},"item_access_right":{"attribute_name":"アクセス権","attribute_value_mlt":[{"subitem_access_right":"open access","subitem_access_right_uri":"http://purl.org/coar/access_right/c_abf2"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorAffiliations":[{"affiliationNameIdentifiers":[],"affiliationNames":[{"affiliationName":""}]}],"creatorNames":[{"creatorName":"兪, 周炫","creatorNameLang":"ja"},{"creatorName":"YU, Juhyeon","creatorNameLang":"en"}],"familyNames":[{},{}],"givenNames":[{},{}],"nameIdentifiers":[{}]}]},"item_files":{"attribute_name":"ファイル情報","attribute_type":"file","attribute_value_mlt":[{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2018-06-06"}],"displaytype":"detail","filename":"A423.pdf","filesize":[{"value":"5.2 MB"}],"format":"application/pdf","licensetype":"license_note","mimetype":"application/pdf","url":{"label":"A423","objectType":"fulltext","url":"https://muroran-it.repo.nii.ac.jp/record/9692/files/A423.pdf"},"version_id":"6e38b7a7-de03-4ba7-bb18-d387addfc6f6"},{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2018-06-06"}],"displaytype":"detail","filename":"A423_summary.pdf","filesize":[{"value":"274.8 kB"}],"format":"application/pdf","licensetype":"license_note","mimetype":"application/pdf","url":{"label":"A423_summary","objectType":"abstract","url":"https://muroran-it.repo.nii.ac.jp/record/9692/files/A423_summary.pdf"},"version_id":"c23d9762-cb89-423b-b723-30d5be9bf2d8"}]},"item_language":{"attribute_name":"言語","attribute_value_mlt":[{"subitem_language":"jpn"}]},"item_resource_type":{"attribute_name":"資源タイプ","attribute_value_mlt":[{"resourcetype":"doctoral thesis","resourceuri":"http://purl.org/coar/resource_type/c_db06"}]},"item_title":"円筒形状を有する長繊維強化セラミック複合材料の機械特性評価法に関する研究","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"円筒形状を有する長繊維強化セラミック複合材料の機械特性評価法に関する研究","subitem_title_language":"ja"}]},"item_type_id":"81","owner":"18","path":["227"],"pubdate":{"attribute_name":"PubDate","attribute_value":"2018-06-06"},"publish_date":"2018-06-06","publish_status":"0","recid":"9692","relation_version_is_last":true,"title":["円筒形状を有する長繊維強化セラミック複合材料の機械特性評価法に関する研究"],"weko_creator_id":"18","weko_shared_id":-1},"updated":"2024-01-22T02:39:52.123522+00:00"}