不同织构形式硬质合金表面与木材径切面的摩擦性能

Study on friction performance between wood radial section and cemented carbide surface with different micro-textures

合理的微坑型微织构已被证明具有改善木材和硬质合金表面间的摩擦特性。采用微凹坑型织构、微凹槽织构和微网格型织构3种织构形式,在相同织构面积占有率条件下,通过摩擦特性试验与理论分析相结合,研究不同织构形式对木材表面摩擦系数的影响。研究表明:在相同织构面积占有率条件下,不同织构的类型和表面形貌对硬质合金试样与木材表面摩擦的摩擦系数有不同的影响,受摩擦长度、凹槽微织构宽度、微织构角度等织构参数的影响。当微织构与木材发生摩擦时,摩擦区域织构面积越大说明两者间实际接触面积越小,且面积越大,捕捉磨屑和硬质点的能力越强;而主制动力越小,其产生的摩擦系数越小。在相同压力和织构面积占有率条件下,不同类型的织构试件与木材表面产生的摩擦系数均小于非织构(平面)型表面产生的摩擦系数。其中:微坑型织构产生的表面摩擦系数最小,为0.116;凹槽型织构产生的表面摩擦系数最大,为0.182;网格型织构随着织构角度的减小,其产生摩擦系数越小。

Reasonable micro-pit texture has been proved to be able to improve the friction characteristics between wood and cemented carbide.In this paper,the influence of micro-pit texture,micro-groove texture and micro-grid texture on friction coefficient was investigated.Under the condition of the same texture area occupancy,the influence of different texture types on the friction coefficient of wood surface was studied by the friction characteristic test.The results showed that the friction coefficient between the cemented carbide and wood surface was influenced by the texture type and surface morphology under the same texture area occupancy,and the friction length,the width of micro-texture and the angle of micro-texture would affect the texture parameters.When the friction occurred between the micro-textured specimens and the wood,the larger friction area with textured,the smaller the actual contact area between the wood and texture surface,and the larger the area,the stronger the ability to capture wear debris and harder points were obtained.The smaller the main braking force was,the smaller the friction coefficient was achieved.Under the condition of the same texture area occupancy,the friction coefficient between the different types of textured specimens and the wood surface was smaller than that between the non-textured surface and the wood.The surface friction coefficient of micro-pit texture was the smallest,presenting as 0.116.The surface friction coefficient of the micro-groove texture was the largest,giving as a value of 0.182.The micro-grid texture had the smaller friction coefficient with the decrease of the texture angle and the friction coefficient was between 0.134 and 0.151.The aims of this study were to improve the friction characteristics between wood and cemented carbide surfaces,reduce the surface friction coefficient,and find the best texture form.The results of this study can provide reference and guidance for the design of more reasonable surface texture form of wood cutting tools.