열경화성 복합재를 이용한 헬기용 블레이드 성형에 관한 연구

Abstract

The purpose of this study was to identify the characteristics of thermosetting composite materials and the optimum conditions of the helicopter blades molding process. The characteristics of thermosetting composite were investigated through the simulation and experiment. As a results, The carbon-epoxy prepreg TSN125 used for helicopter blades had optimal molding temperature, 126℃. And this temperature was approaching required specifications that showed proper temperature at a fast curing point and efficiency. The structural stability of the blade mold of SS400 material was confirmed by structure analysis. In the results of structure analysis, the deformation of mold was occurred as 0.03~0.2㎛. But the mold without structure deforms to over 60㎛. The maximum compressive stress of mold with structure was distributed as 0.402~1.18MPa. The tensile strength, as 0.191~0.367MPa, was higher than conventional material properties. The dimension of mold and blade was evaluated by the 3-axis coordinate measurement machine of Hexagon lambda 706030. The dimensional errors was distributed within the range of tolerance. The mold measurement results to Y-axis length direction from the reference point has maximum (+) error 0.05mm at 1619.70mm and maximum (-) error 0.057 mm at 6619.70mm. The blade measurement results has maximum (-) error 0.1425mm at 1619.70mm and minimum (-) error 0.009mm at 6619.7mm point. At maximum (+) error part of mold, the blade showed the maximum (-) error. The change of thickness of blade was caused by shrinkage and pull of resin. Thus, the amount of Epoxy filled in cavity between mold and thermosetting composite materials affected the dimensional accuracy of blade.