자동차 내장 폴리머 재료의 열화모델 개발

다국어 초록 (Multilingual Abstract)

In the automotive industry, rattle noise is one of the important issues, which occurs in the cockpit or other interior components when the parts in close proximity impact against each other under the excessive vibration. As more polymers are employed in these parts and the polymer is prone to degradation, the noise becomes more pronounced in the aged cars. Diverse efforts are being directed to solve these problems, one of which is to conduct FEA to simulate rattle occurrence. In this study, degradation of the material properties is investigated for the polymers of the automotive, which includes elastic modulus, Poisson ratio and CTE on the static side and storage and loss moduli on the dynamic side. Empirical models are established that describes the degradation behavior as a function of time as well as the temperature and humidity, by using some suitable models including Arrhenius and Layton models. In order to account for the scattered data, statistical techniques are employed which are the maximum likelihood and bootstrap methods, from which the model is obtained in the form of probability distributions. Once the models are established, they are used to predict the degradation under arbitrary cycles by applying the concept of cumulative degradation which is given by the integration of the degradation rate over time. Finally, the prediction is validated by applying arbitrary cycles to the coupon, measuring the property and comparing with the predicted values.

목차 (Table of Contents)

• Abstract
• 1. 서론
• 2. 폴리머 열화모델 개발
• 3. 가상의 데이터를 이용한 방법론 시현 및 입증
• 4. 결론
• 참고문헌