ABSTRACT

The cutting process of oak (Quercus robur) was investigated by means of a novel testing approach. A unique testing device, enabling nearly linear stand-alone cuts, was used. The specimens climatized to 6 different moisture content levels were machined within cutting velocities ranging from 5 to 80 m·s⁻¹, at 5 cutting fibre angles from along to across the grain, and at different uncut chip thicknesses of up to 0.5 mm. The precise quartz sensor utilized for observing cutting forces enabled insights into the cutting mechanism involved while wood disintegration. Cutting velocity evolved as a key process parameter strongly influencing cutting force. Evaluation of uncut chip thickness showed a regression that was strongly influenced by particular force components. The friction force generated by “ploughing” the surface was relevant when cutting thin chips. In contrast, the part of force introduced by chip formation affected the process weightily in the case of cutting a thick chip. When cutting parallel to the grain lower forces were observed than cutting perpendicular to grain orientation. Obtained data supported the mathematical force prediction model establishment involving several parameters (e.g. cutting velocity, cutting fibre angle, uncut chip thickness, and moisture content).

摘要

通过一种新颖的测试方法研究了橡木(Quercus robur)的切割过程。使用了一种独特的测试设备，可实现近乎线性的独立切割。^{在 5 至 80 m·s −1}的切削速度范围内加工适应 6 种不同含水量水平的试样, 在 5 个切割纤维角度下，从沿纹理到横过纹理，以及在不同的未切割切屑厚度下，厚度可达 0.5 毫米。用于观察切割力的精确石英传感器能够深入了解木材分解时所涉及的切割机制。切削速度演变为强烈影响切削力的关键工艺参数。对未切割切屑厚度的评估显示了受特定力分量强烈影响的回归。切削薄切屑时，“犁过”表面产生的摩擦力很重要。相比之下，在切割厚切屑的情况下，切屑形成引入的部分力对工艺影响很大。当平行于晶粒切割时观察到比垂直于晶粒方向切割更低的力。