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优质乐器的需求与日俱增,但是性能优良的木材有限,为了对木材进行声学性能改良、减少优良木材的需求压力,本文以人工林杉木为试材,采用超声波、热处理及超声波-热处理结合工艺对改善木材声学性能进行了探究。结果表明,在超声280w、340w、400w,时间分别为8min、9min、10m i n条件下,随超声处理功率和时间的增加,木材的声学性能改善先增加后降低,超声处理主要改善木材对数衰减系数;从120℃~220℃,随热处理温度升高,木材结晶度与比动弹性模量明显提高,同时对数衰减系数降低。速生杉木声学性能改良的优化处理条件为:400W,8min,220℃,保温30min,且改良杉木声学性能效果接近陈放古木。超声波处理及高温热处理对杉木化学成分含量及声学性能参数均有一定的影响,可以通过降低木材中抽提物、提高木材的纤维素结晶度来改善木材的声学性能。
In order to improve the acoustic performance of wood and reduce the pressure on the demand of fine wood, this paper takes the artificial forest Chinese fir as the test material, using ultrasonic, heat treatment and ultrasonic-heat treatment combined process to improve the wood Acoustic performance was explored. The results showed that the acoustic performance of wood increased firstly and then decreased with the increase of ultrasonic power and time under ultrasonic wave of 280w, 340w, 400w for 8min, 9min and 10min respectively. Ultrasonic treatment mainly improved the logarithmic decrement of wood From 120 ℃ to 220 ℃, with the increase of heat treatment temperature, the crystallinity and specific elastic modulus of wood increased obviously, while the logarithmic attenuation coefficient decreased. Acoustic properties of fast growing Chinese fir optimized processing conditions: 400W, 8min, 220 ℃, holding 30min, and improve the acoustic properties of Chinese fir close to the ancient Chen. Ultrasonic treatment and high temperature heat treatment have certain influence on the chemical composition and acoustic performance parameters of Chinese fir, and can improve the acoustic performance of wood by reducing the extract of wood and increasing the cellulose crystallinity of wood.