The cutting of tea stalks is one of the most used measures for mechanized pruning and plucking which enlarge canopies and increase shoots. It is of importance to obtain the mechanical property of tea stalks in order to understand and improve cutting process, cutter design and cutting performance. The mechanical property parameters of different parts along tea stalks were measured through bend and shear testing. Loading stiffness, unloading stiffness and plastic deformation difficulty level were defined and used together with bending energy to evaluate difficulty level of bending and plastic deformation. The results showed that along the height of 410 mm to 760 mm, (I) stem diameter decreased from 5.37 to 2.05 mm, however, maximum moisture content appeared on the height of 560 mm; (2) loading stiffness and unloading stiffness decreased from 6.5 to 0.156 N-mmr'and from 8.96 to 0.38 N-mmr1, respectively; (3) plastic deformation difficulty level decreased from 0.6 to 0.016 N-mm'2, and bending energy also decreased from 0.09 to 0.003 J; (4) maximum shearing force, shearing stress, shearing energy and specific shearing energy decreased from 175.3 to 2.3 N, from 8.53 to 0.69 MPa, from 0.49 to 0.002 J and from 22.6 to 0.7 mJ-mm2, respectively.
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