摘要：本文以片状结构云母为主要功能填料，辅以适量的超细CaCO3，以纯丙乳液为基体材料通过共混法制备了阻尼浆。通过阻抗管法和多通道数据采集系统研究了阻尼浆的阻尼隔声特性及其对动车组铝型材阻尼隔声特性的影响，还对其影响机理做了进一步分析。研究结果表明：制备的阻尼浆具有优异的阻尼损耗特性，将其涂敷在铝板上可明显提高隔声性能；在动车组铝型材车体上分别涂敷2mm、4mm阻尼浆涂层，模态阻尼比可分别显著提高200%和400%，计权隔声量可分别提高4.5dB和6.9dB。
关键词：阻尼浆；云母；铝型材；隔声；阻尼
Abstract: In this paper, mica as the main function of the filler, with proper amount of ultrafine CaCO3, and acrylic acid emulsion as matrix material, damping coating was prepared by blending slurry. The damping and sound insulation were tested through impedance tube method and multi channel data acquisition system. It is also studied that the sound insulation of high speed train Aluminum profile which was affected by damping coatings. The results show that: the damping slurry has excellent damping properties, the coating on the aluminum plate can significantly improve the sound insulation performance; aluminum body were coated with 2mm, 4mm damping coating, modal damping increased 200% and 400%, Sound insulation property can increase 4.5dB and 6.9dB respectively.
Key words: Damping coating, Mica, Double structure aluminium section, Sound insulation, Damping
1.引言
动车组多采用双层薄壁铝合金作为车体结构，该结构具有质量轻，结构稳定，整体耐腐蚀性强等诸多优点。但由于双层薄壁铝合金的层与层之间为维持结构稳定添加了起支撑作用的筋，导致大量噪声沿固体传播；筋与两侧的铝合金壁形成了若干空腔，也使一部分噪声通过空气传播[1]；双层薄壁铝合金的结构特点及铝材质本身的特性使其隔声性较差，噪声在双层薄壁铝合金结构中的传播途径如图1所示。
为了改善铝型材的隔声性能，可通过改善筋及薄壁部分的阻尼性能，抑制其振动，从而降低噪声的产生和传播。通常采用在筋及薄壁的一侧粘贴阻尼材料以增强其阻尼[2,3]。基于此，本论文以制备具有优异阻尼损耗特性的阻尼浆为基础，将其应用于动车组铝型材表面，研究其对铝型材隔声性能的改善作用，并分析其机理。
作者：曾要争