基于压电传感技术的中密度纤维板弹性模量检测  

Detection on the modulus of elastic of medium density fiberboard using piezoelectric sensing technology

作　　者：王宇轩 王晓羽 席靖宇 徐兆军 王新洲 WANG Yuxuan;WANG Xiaoyu;XI Jingyu;XU Zhaojun;WANG Xinzhou(College of Materials Science and Engineering,Nanjing Forestry University,Nanjing 210037,China)

机构地区：[1]南京林业大学材料科学与工程学院,南京210037

出　　处：《林业工程学报》2024年第6期78-85,共8页Journal of Forestry Engineering

基　　金：江苏省自然科学基金(BK20180774)。

摘　　要：中密度纤维板是一种广泛应用的人造板材料,弹性模量是衡量其力学性能的重要指标。提出并验证了一种基于压电传感技术的中密度纤维板动态弹性模量无损检测方法,并与应力锤敲击法和静态三点弯曲法进行了对比。该方法通过利用压电晶片的压电效应对试件施加激励信号,并调整信号频率以使其与试件共振,从而得到试件的固有频率、弹性模量等振动性能参数。选用7种不同厚度(8~25 mm)的普通型干燥状态下的纤维板作为试验材料,对每种厚度的纤维板分别测量了其前三阶动态弹性模量,并与静态弹性模量进行了比较分析。结果表明,压电振动法测得的一阶和二阶动态弹性模量与静态弹性模量之间的相关系数分别为0.92和0.93,而应力锤敲击法测得的一阶和二阶动态弹性模量与静态弹性模量之间的相关系数分别为0.87和0.89。这说明压电振动法在测量中密度纤维板动态弹性模量方面具有很高的准确性和可靠性,且优于应力锤敲击法。此外,还探讨了不同厚度和不同阶数对动态弹性模量测量值的影响,发现低阶动态弹性模量更能代表中密度纤维板整体的动态弹性模量值;随着厚度的增加,中密度纤维板的动态弹性模量也会增加,这与静态弹性模量的变化趋势一致。本研究为中密度纤维板的材料特性研究提供了一种有效且可靠的无损检测方法。Medium density fiberboard(MDF) is a widely used wood-based board material,and the modulus of elasticity is an important indicator of its mechanical properties.This study proposed and validated a non-destructive testing method for the dynamic modulus of elasticity of MDF using piezoelectric sensing technology and compared it with the measurement results using the stress hammer impact method and the static three-point bending method.This method applied an excitation signal to the test piece by utilizing the piezoelectric effect of the piezoelectric wafer,adjusted the signal frequency to resonate with the test piece,transmitted the collected signals to the upper computer software through the data acquisition card,and finally performed the fast Fourier analysis in the upper computer software to obtain the natural frequency of the test piece,and then calculated the modulus of elasticity by substituting the natural frequency into the theoretical formula.In this study,seven kinds of ordinary type fiberboards with different thicknesses(8-25 mm) under dry conditions were selected as test materials,and the modulus of elasticities of MDFs with deferent thickness specifications were measured using the piezoelectric vibration method,the stress hammer impact method,and the static three-point bending method,and then compared with the measured dynamic and static modulus of elasticity.The test results showed that the correlation coefficients between the first and second order dynamic modulus of elasticity measured by the piezoelectric vibration method and the static modulus of elasticity were 0.92 and 0.93,respectively,while the correlation coefficients between the first and second order dynamic modulus of elasticity measured by the stress hammer impact method and the static modulus of elasticity were 0.87 and 0.89,respectively.The results indicated that the piezoelectric vibration method had high accuracy and reliability in measuring the dynamic modulus of elasticity of MDF,which were superior to the results obtained by the stre

关 键 词：中密度纤维板 动态弹性模量 压电传感技术 无损检测 

分 类 号：S781.2[农业科学—木材科学与技术]