@techreport{oai:jaxa.repo.nii.ac.jp:00047163,
 author = {安岡, 哲夫 and 竹澤, 正仁 and 平野, 義鎭 and 松尾, 宏平 and 櫻井, 昭男 and YASUOKA, Tetsuo and TAKEZAWA, Masahito and HIRANO, Yoshiyasu and MATSUO, Kohei and SAKURAI, Akio},
 month = {Dec},
 note = {本研究では，複曲率を有する航空機複合材部材に曲率線に基づく展開成形技術を適用することを提案する．複曲率を有する曲面は伸縮なく平面展開することができない非可展面であるため，2次元の平面形状であるプリプレグテープをレイアップすると，本質的に繊維のしわや，トウのすき間・重なりといった欠陥の発生を避けることができず，これらの欠陥は剛性および強度低下の要因となる．本研究では，曲率線展開成形技術の航空機CFRP構造への適用性について検討した．具体的には，曲率線配置を行い，曲率線を基準線として曲面を2次元平面に展開し，展開平面を用いてオートクレーブ法による成形試作を行いその結果を評価した．非可展面を有する3種類の形状について検討を行った．まず，曲率変化が緩やかな自動車のエンジンフードと，ウィンドシールド周りで急激な曲率変化を有する航空機の機首外板については，曲率線を部材表面に配置することができ，また2次元平面形状に展開することができた．さらに，織物プリプレグシートを展開平面形状に切断し，成形型に積層し，オートクレーブ法により硬化させた結果，しわやボイドもなく高品質に成形することができ，当該技術の有効性を確認できた．また，折れ曲がり部が複曲率の表面となっている曲面フランジを有するスパーについても検討を行った．この部材については，曲率線配置および2次元平面への展開は成功したものの，得られた展開形状は複合材成形に不向きであり，このような折れ曲がり部を有する部材については複合材成形への効果は限定的であると考えられた．, In this study, a novel manufacturing technique using orthogonal principal strips based on lines of curvature applicable to aircraft composite parts having double curvature surfaces was proposed. A double curvature surface is non-developable; it is difficult to layup intrinsically two-dimensional prepreg tapes on such a surface without any fiber wrinkles, gaps and laps of tows, which induce stiffness and strength degradation of the resulting product. The applicability of this technique was investigated by arranging the orthogonal nets based on lines of curvature onto non-developable surfaces, unfolding the orthogonal principal strips into the two-dimensional shapes and molding several types of composite parts from those strips. Three types of the parts with non-developable surfaces were considered: an engine hood of automobile, aircraft nose/cockpit skins and a spar with curved surface flanges. The orthogonal nets were successfully arranged on both the engine hood with no steep change of curvature and the aircraft nose/cockpit skins with steep change of curvature around windshield, and unfolded into the two-dimensional shapes. Then the prepreg sheet of woven fabric was cut into the unfolded shapes, stacked onto a mold, and cured with an autoclave process. The resulting composite parts were successfully manufactured with high quality, no wrinkles and voids. In other words, the proposed technique is effective composite manufacturing method. On the other hand, regarding the spar with curved surface flanges, which consisted of developable flange/web surfaces and an undevelopable flange/web joining part surface, the orthogonal net was also successfully arranged on the surfaces and unfolded into the orthogonal strips; however, it was considered that the obtained unfolded strips were not suitable for prepreg tapes cutting and composite molding. It was concluded that the scope of application of the proposed method is limited for this type of surfaces with joining parts., 形態: カラー図版あり, Physical characteristics: Original contains color illustrations, AA2030006000, レポート番号: JAXA-RR-20-002},
 title = {曲率線展開成形の航空機CFRP構造への適用},
 year = {2020}
}