剑麻切割应力力学性能

Mechanical Properties of Sisal Cutting Stress

以成熟的、生长状况相似的剑麻（Agave sisalana Perr.ex Engelm.）叶片为研究对象,利用WD-200B微机控制电子万能试验机,采用单因素试验法测得不同影响因素下最大切割应力,并分析了切割速度、切割部位、切割叶面、切割方式、切割角度、含水率对切割应力的影响。结果表明,切割剑麻主要影响因素有切割角度、切割方式以及切割叶面部位。在100 mm/min速度下切割收集的剑麻根部的侧面部位,侧切较正切和背切的剪切应力小为0.521 MPa;在250 mm/min速度下取不同含水率最高时应力最小为0.476 MPa;取侧面部位削切的角度为30°~45°区间内,应力区间为0.330~0.352 MPa。该结果为剑麻的收割机械研制时切割位置、切割时间、切割器及刀具的设计、电动机功率的选取等方面提供数据支持。

Studying the mechanical properties of Sisal leaf gives basic idea of Sisal harvester design and development. To analyze the properties of Sisal leaf shear stress under different stress conditions, we took cutting speed,leaf height,cutting position of leaf surface,cutting mode,cutting angle and moisture content as factors. Mature Sisal leaves with identical growing condition as the research object was chose. Using computer control electronic universal testing machine, the maximum shear stress was supposed to be measured and the effect was analyzed through single-factor controlled experiment. The results showed that the main factors affecting cutting sisal were cutting angle,cutting mode and cutting position of leaf surface. The lower part of the fresh leaves with the highest moisture content was chose. The shear stress was measured in three different parts of sisal leaf —the side,front and the back part. The stress at the side was minimum, which was 0.521 MPa with lower part of the Sisal leave edge being cut. The stress was 0.476 MPa under maximum moisture content. If the cutting angle towards the side part lay within range of 35°~40°,the corresponding stress varied from 0.330 to 0.352 Mpa. The analytical results offered the experimental data required for sisal harvester technology development.