不同压缩加载速度对杉木微观结构和力学性能影响

Effect of Loading Rate on Microstructure Characteristics and Mechanical Properties of Chinese Fir

摘要:

以典型针叶材树种杉木(Cunninghamia lanceolata)为研究对象，采用微型力学试验装置和自主研发的原位检测系统，在1，10，50mm/mim加载速度条件下，研究木材连续横纹压缩时的力学行为差异和微观结构的实时变化.结果表明：在不同加载速度条件下，木材出现首次屈服变形的位置不同，这将直接导致木材力学行为产生差异；原位检测系统可以准确地表征木材微观结构的变化特征，从而可以很好地解释不同加载速度下木材产生力学行为差异的原因.

Abstract:

In order to elucidate the mechanical properties and microstructure characteristics of typical soft wood of Chinese fir(Cunninghamia lanceolata) during continuous transverse compression, micro mechanical tester and a self developed in situ inspecting system were applied. Loading rates of 1,10,50 mm/mim were adopted respectively for mechanical testing of wood. The results indicate that the variations of wood mechanical properties at different loading rates are generated from the different position of the first yield point. The in situ inspecting system can accurately characterize the variations of microstructure. Furthermore, the microstructure characteristics can be used to explain mechanical behavior of wood under different loading rates.