Application of the Birefringent-Coating Method to CFRP

• Material Type: 文書・図像類
• Title: Application of the Birefringent-Coating Method to CFRP
• Author/Editor: 越出, 慎一; KOSHIDE, Shinichi
• Author Heading: 越出, 慎一; KOSHIDE, Shinichi
• Publication, Distribution, etc.: 航空宇宙技術研究所
• Publication Date: 1990-10
• Publication Date (W3CDTF): 1990-10
• Alternative Title: 光弾性被膜法のCFRPへの応用
• Periodical title: 航空宇宙技術研究所報告 = Technical Report of National Aerospace Laboratory TR-1085
• No. or year of volume/issue: 1085
• Volume: 1085
• Pages: 25-
• ISSN (Periodical Title): ISSN : 0389-4010
• Text Language Code: eng
• Target Audience: 一般
• Note (General): The objective of this investigation is to analyze the stress and strain distributions along the boundary in structural parts of the composites, such as carbon-fiber reinforced plastics(CFRP), by the birefringent-coating method. However, there some problems in using the method for strain analysis of CFRP, because appearances and mechanical properties of the materials were not suitable for such application. In this investigation, the problems are solved by introducing the following experimental processes. (1)A process for viewing the isochromatic fringe patterns using the reflected light from the adhesive layer with which aluminium powder has been mixed. (2)A process for analysis of strain components by substituting the relation between the fringe order of the isochromatic fringe patterns and principal strain differences into the Poisson's ratio for an anisotropic material. These processes were applied to strips of CFRP with a circular hole under tension as an experimental demonstration. In this paper, the adequancy of the method and the peculiarity of strain distributions in the strips of CFRP are discussed with reference to the results of the experiment. Strain values at a point on the circular hole boundary in the strip which were analyzed by the method and those which were analyzed by the moire method almost agree. The agreement corrobrates that either method is adequate for strain analysis. Strain distributions around the hole of the CFRP strips differ from these of isotropic materials such as metals. These distributions are also greatly influenced by the fiber-orientation-to-load-direction. Stresses in the structural parts of composites can be determined from the strain distributions described above and the stress-strain relation for an anisotropic material. Stress distributions in the strip of CFRP with a circular hole are also shown as an example. The appropriate results of the example are confirmed agreement with the theoretical solutions for a composite plate with a circular hole under tension. Moreover, the birefringent-coating method applies to stress and strain analysis for CFRP joint specimens under pin load. Analysis of the joint is very important to subassemblies of aircraft made of composites, because the bolted joint subjected to pin load is used to connect the subassemblies. The experimental results for the joint make it clear that the stress and strain distributions in composites under partial load are also different from those of isotropic materials. Fiber-orientation-to-pin-load-direction influences the stress and strain distributions in the CFRP joint.; 資料番号: NALTR1085000; レポート番号: NAL TR-1085
• Access Restrictions: 限定公開
• Data Provider (Database): 国立情報学研究所 : 学術機関リポジトリデータベース（IRDB）（機関リポジトリ）; https://irdb.nii.ac.jp
• Original Data Provider (Database): 宇宙航空研究開発機構 : 宇宙航空研究開発機構リポジトリ