On the Measurement of Strain Distribution in Wood under the Axial Tension Force by X-Ray Diffraction
On the Measurement of Strain Distribution in Wood under the Axial Tension Force by X-Ray Diffraction
复制标题
X射线衍射法测量轴向拉力下木材应变分布
DOI：
10.2472/jsms.20.1188
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发表时间：
1971
期刊：
影响因子：
--
通讯作者：
I. Asano
中科院分区：
文献类型：
--
作者：
N. Sobue;N. Hirai;I. Asano
在纤维方向的轴向拉力作用下，利用纤维胶束的(040)反射X射线衍射法测量了纤维(I)在管胞细胞壁b轴方向上的晶格应变分布。本研究采用中转X射线法，通过40秒的固定时间和θ-2θ方法获得了衍射图。用粘贴在试件两侧的电应变仪和电阻式应变片测量了试件沿纤维方向的宏观表面应变，纤维方向的晶格应变略小于试件的表面应变，但晶格应变与表面应变的平均比值在3,000×10-6的表面应变水平以下为0.90∼-0.97。结果表明，细胞壁上排列的胶束实际上承担了一部分外加应力，并对木材的力学性能起到了有效的作用。定性地观察到，胶束沿纤维方向的轴向拉伸大大改善了胶束的取向。
Under the axial tensile force in the fiber direction the distribution of crystal lattice strain in the b-axis direction of the cellulose (I) in the cell wall of tracheids were measured by the X-ray diffraction technique using (040) reflection of cellulose micelles.In this study the transit X-ray method was used and the diffraction profiles were obtained by 40sec fixed time and θ-2θ method. The macroscopic surface strains of the specimens in the fiber direction were measured by the electrical strain meter and resistance type strain gage, pasted on both sides of the specimens.The lattice strain in the fiber direction was a little smaller than the surface strain of the specimens, but the average ratio of the lattice strain to the surface strain was in the range of 0.90∼0.97 below the surface strain level of 3000×10-6.The lattice strains decreased with the increasing inclination from the fiber axis.In the inclined direction from the fiber axis, the lattice strains were a little smaller than the normal strains of the specimen calculated from Eq. (10), of homogeneous orthogonal anisotropic body, but the appearance of distribution of lattice strains in the cell wall was similar to that of the normal strains of the specimens.From those results it is considered that the micelles which were arranged in the cell wall have actually taken over a portion of the applied stress and acted an effective role in the mechanical properties of wood.It is qualitatively observed that the micelles have largely been improved in their orientation by the axial extension in the fiber direction.