단방향 카본/열가소성 테이프의 하이브리드 공법을 이용한 경량화 복합소재 엔진 브라켓 개발

Abstract

Globally, environmental regulations for various industries are becoming increasingly strict due to global warming. In particular, as the demand for eco-friendly cars increases, interest in fuel efficiency improvement and emission reduction through lightweight of vehicles is increasing. Research is being actively conducted to develop automobile parts using fiber-reinforced plastic composites, which have the advantages of low density, high specific strength and stiffness. However, since chassis parts of automobiles are very complicated in shape, the research on weight reduction using composite materials is insufficient. Therefore, this study carried out research to replace steel engine bracket with composite materials(Carbon/PA6) among automobile chassis parts. Since engine bracket have different shapes and weights according to the types of engines, three engine brackets have been developed for each model.

The engine bracket connects the engine and the engine, is a key component to reduce the noise and vibration transmitted from the engine. Therefore, structural stability, noise and vibration characteristics must be satisfied simultaneously. The purpose of this study is to develop a 50% lighter product than conventional steel, and to compare NVH performance with steel engine brackets through free-free and actual vehicle fixed modal tests, and to ensure correlation between experimental and analytical results. It is difficult to manufacture using general-purpose materials according to the product shape, so it is manufactured by chopped Carbon/PA6 UD Tape and hybrid material method mixed with Skeleton(Continuous Tape). In addition, the metal insert was processed to increase driving performance. Composite Engine Bracket was installed on the car to evaluate the driving performance and confirmed that it is the same level as the steel engine bracket.| 전 세계적으로 지구온난화에 따른 다양한 산업에 대한 환경규제가 점차 엄격해지고 있다. 특히 친환경 자동차에 대한 요구가 높아지는 현재, 차량의 경량화를 통한 연비 개선 및 배기가스 감소에 대한 관심이 높아지고 있다. 그중 낮은 밀도 특성, 높은 비강도, 비강성의 장점을 가지고 있는 섬유강화 플라스틱 복합소재를 활용하여 자동차 부품을 개발하기 위한 연구가 활발히 진행

되고 있다. 그러나 자동차의 샤시 부품은 형상이 매우 복잡하기 때문에 복합소재를 활용한 경량화 연구가 미진한 수준이다. 따라서 본 연구에서는 자동차샤시 부품 중 스틸 엔진 브라켓을 복합소재로(Carbon/PA6) 대체 개발하는 연구를 진행하였다. 엔진 브라켓은 엔진의 종류에 따라 그 형상과 중량이 다르므로 각 모델에 따른 3가지 엔진 브라켓을 개발하였다.

엔진 브라켓은 엔진과 엔진 마운트를 연결하며 엔진에서 전달되어 오는 소음, 진동을 저감 시켜주는 핵심 부품이다. 따라서 구조적 안정성, 소음, 진동 특성을 동시에 만족해야 한다. 본 연구의 목적은 기존의 스틸 대비 50%의 경량화된 제품을 개발하는 것이 며, 자유단, 실차 모달 실험을 통해 기존의 스틸 엔진 브라켓 대비 NVH 성능을 비교하고 실험 결과와 해석 결과의 상관성을 확보하는 것이다. 제품의 형상에 따라 범용화된 소재를 사용하여 제작하기에 어려움이 있어 Carbon/PA6 UD Tape을 잘게 자른 것과, Skeleton(Continuous Tape)을 혼합한 하이브리드 소재 공법으로 제작 하였고, 주행성능을 증가시키기 위해 Metal Insert를 추가로 진행하였다.

이렇게 제작한 것을 바탕으로 차에 장착하여 주행성능을 평가하였고 스틸 엔진 브라켓과 동일 수준의 성능임을 확인하였다.; Globally, environmental regulations for various industries are becoming increasingly strict due to global warming. In particular, as the demand for eco-friendly cars increases, interest in fuel efficiency improvement and emission reduction through lightweight of vehicles is increasing. Research is being actively conducted to develop automobile parts using fiber-reinforced plastic composites, which have the advantages of low density, high specific strength and stiffness. However, since chassis parts of automobiles are very complicated in shape, the research on weight reduction using composite materials is insufficient. Therefore, this study carried out research to replace steel engine bracket with composite materials(Carbon/PA6) among automobile chassis parts. Since engine bracket have different shapes and weights according to the types of engines, three engine brackets have been developed for each model.

The engine bracket connects the engine and the engine, is a key component to reduce the noise and vibration transmitted from the engine. Therefore, structural stability, noise and vibration characteristics must be satisfied simultaneously. The purpose of this study is to develop a 50% lighter product than conventional steel, and to compare NVH performance with steel engine brackets through free-free and actual vehicle fixed modal tests, and to ensure correlation between experimental and analytical results. It is difficult to manufacture using general-purpose materials according to the product shape, so it is manufactured by chopped Carbon/PA6 UD Tape and hybrid material method mixed with Skeleton(Continuous Tape). In addition, the metal insert was processed to increase driving performance. Composite Engine Bracket was installed on the car to evaluate the driving performance and confirmed that it is the same level as the steel engine bracket.