공중합 아라미드는 기존의 파라계 아라미드의 단점인 낮은 신축성을 개선한 섬유로서 굴곡 성능이 우수한 특성을

갖고있지만 굴곡피로 성능을 평가할 수 있는 평가법은 부재한 실정이다. 현재 국내에서는 공중합 아라미드 개발을 위

해 다양한 연구가 진행되고 있으며 아라미드의 신뢰성을 세계적 수준까지 발전시키기 위해서는 굴곡성능을 평가할 수

있는 평가법 개발이 필요한 상황이다. 본 연구에서는 공중합 아라미드의 굴곡피로성능을 평가할 수 있는 평가장치와

평가법을 개발하고 아라미드의 굴곡피로성능을 분석하였다. 굴곡피로시험기의 굴곡부는 마찰을 최소화 하기 위해 롤

러 재질을 세라믹 재질로 선정하였으며 롤러 형태는 회전형태로 제작하였다. 롤러의 직경은 최소허용곡률을 계산하여

10 mm로 선정하였다. 굴곡피로시험을 통해 B10 수명을 산출하였으며 파라계 아라미드는 125,770회, 공중합 아라미드

598,150회, ANF(Aramid Nano Fiber)로 표면처리한 공중합 아라미드는 589,073회로 나타내었다. S-N선도를 통해 하

중 변화에 따른 피로 수명 관계를 파악하였으며 고하중 조건에서도 공중합 아라미드 가 파라계 아라미드 보다 우수한

굴곡피로 성능을 나타내고 ANF로 표면처리한 공중합 아라미드 또한 우수한 굴곡 피로 성능을 나타내는 것을 확인하였다.

Although copolymer aramid is a fiber with excellent flexural performance, there is no test method to

evaluate flexural fatigue performance. Various studies are currently being conducted in korea to develop copolymer

aramid, and in order to develop the reliability of aramid fibers to a global level, it is necessary to develop a test method

to evaluate the flexural fatigue performance of aramid fibers. In this study, we developed an test equipment and test

method that can evaluate the flexural fatigue performance of copolymer aramid and analyzed the flexural fatigue

performance of aramid fiber. Flexing rollers are made of ceramic materials and rotating shapes to minimize friction. The

diameter of the roller was set to 10 mm by calculating the minimum allowable curvature. The B10 life was calculated

through a flexural fatigue test, and the para-aramid was 125,770 cycles, the copolymer aramid was 598,150 cycles, and

the aramid nano fiber(ANF) coated copolymer aramid was 589,073 cycles. Through the S-N diagram, the fatigue life

relationship according to the load change was confirmed. copolymer aramid fibers exhibit better flexural fatigue

performance than para-aramid fibers at high loads. The ANF coated copolymer aramid also exhibits excellent flexural

fatigue performance.

Copolymer aramid, Fiber, Flexural fatigue, Flexing roller, B10 life, Weibull distribution

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