Abstract：
In the acoustics of musical instruments with a resonator body, the aging of the wood leads to the improvement of the acoustic properties due to increasing the crystallinity of wood. This phenomenon could be explained by the fact that wood is a complex product based on three-dimensional polymer chains of carbohydrates, its aging being closely related to covalent cross-linking and scission of polymer chains. The aim of this study was to evaluate at a multiscale the changes produced artificial aging of tone wood by measuring the acoustic, mechanical and chemical parameters. The spruce and maple wood samples were investigated before and after exposure to ultraviolet (UV) radiation, through the tensile test, the time-of-flight method (TOF), the analysis of the wood color and the determination of the chemical fingerprint through Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The obtained results showed that the effects of artificial aging are manifested at the chemical level where the crystallinity increases up to the acoustic level, depending on the wood species and their quality class. These results are relevant for musical instrument manufacturers to find treatments that lead to superior acoustic properties.
摘要：
在具有谐振器主体的乐器的声学中，由于木材结晶度的增加，木材的老化导致声学性能的改善。这种现象可以通过以下事实来解释：木材是基于碳水化合物的三维聚合物链的复杂产品，其老化与聚合物链的共价交联和断裂密切相关。这项研究的目的是在多尺度上评估的变化产生的人工老化的色调木材，机械和化学参数。在暴露于紫外线（UV）辐射之前和之后，对云杉和枫木样品进行了研究，通过拉伸试验，飞行时间法(TOF)，通过傅里叶变换红外光谱(FTIR)和X射线衍射(XRD)对木材进行颜色分析和化学指纹图谱的测定。获得的结果表明，人工老化的影响表现在化学水平，其中结晶度增加到声学水平，取决于木材种类和它们的质量等级。这些结果与乐器制造商找到导致优异声学性能的处理相关。
