| Summary: | 碩士 === 中國文化大學 === 化學工程與材料工程學系奈米材料碩士班 === 104 === Noise control problem has attracted the widespread attention of governments and scientists. The impact of noise on human health can be divided into two parts: 1. Physiological effects: cause the human nervous reaction, adrenaline increases, causing changes in heart rate and blood pressure, causing damage hearing mechanism. 2. Psychological effects: noise easy to feel annoyance, disturbance of sleep. In order to improve the quality of life, we need to reduce noise pollution.
In this experiment, PU Foam and honeycomb structure made of porous fabric binding composite sound-absorbing material. By changing the structure of the plate thickness, pore size, density and sheet strength and acoustic performance testing, as focuses on the project, hoping to make a good mechanical properties and good indoor acoustic sound absorption material.
In the experiment, first on density changes on the structure, the results that PU foam at a fixed volume the greater the density, the smaller the aperture, and the pore size referrals in 0.3mm ~ 0.72mm to have the best sound-absorbing effect.
The honeycomb fabric as a composite sheet of reinforcing material manufacture, testing its mechanical properties and absorbing effect, the test result, the mechanical properties of 3mm best, the density of 0.19 g / cm3, warp and weft impact strength were 88.57Kg-cm, 86.64 Kg-cm. Acoustic performance and unused fabric of honeycomb structure when compared absorbing sheet has more to enhance the effect.
In a further approach to the use of sound-absorbing laminate matching analysis, double match, when to 9mm honeycomb fabric as the first layer of the composite sheet, the best sound-absorbing, the sound-absorbing rate of 0.9 or more. And when using the three-way match acoustical test, due to the overall thickness of the sheet caused by excessive sound absorption rate has dropped the case.
In summary, using 9mm honeycomb fabric manufacture composite sheet, matching the 3mm honeycomb fabric composite sheet can get the best mechanical properties and absorbing effect.
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