Abstract:

The micro groove structures were processed on aluminum alloy surface using high speed micro-milling machine. Setting the values of Ra and Rz as the measurement standard, the surface quality of the groove was studied. The influences of parameters including spindle speed, the overhanging length of cutting tool, feed rate and axial depth of cut were analyzed based on orthogonal experimental method. The results show that the whole varying trend of the surface roughness is that the surface roughness of midline area>that of down milling area>that of up milling area. Spindle speed is the most important influence factor on surface roughness. By contrast, the level of other factors will be changed when the measurement standard of surface quality is different.Compared with other factors which affect the surface roughness differently according to different requirements of surface quality, spindle speed has the most significant influence. In response to the surface qualities' requirements, the results of optimal combination are that Ra is as 0.075μm and Rz is as  0.579 μm when the overhanging length of cutting tool is as 18mm, the axial depth of cut is as 10μm, feed rate is as  30mm/min and the spindle speed is as 48000r/min.

Key words: micro-milling, surface roughness, aluminum alloy, variance analysis

摘要：

利用小型高速精密微铣削机床在6061铝合金表面加工微沟槽结构,对加工后的试件表面质量进行研究,以试件表面粗糙度Ra、Rz值为衡量指标,利用正交试验方法分析主轴转速、刀具悬伸量、进给量和轴向切深等因素对表面质量的影响。试验结果表明：试件表面粗糙度值整体变化趋势从大到小依次为中线区、顺铣区、逆铣区。主轴转速对表面粗糙度影响最显著,而其他因素随着表面质量要求的不同有所变化。综合考虑表面质量要求,最优组合为:刀具悬伸量为18mm,轴向切深为10μm,进给量为30mm/min,主轴转速为48 000r/min时,试件表面粗糙度最小,此时表面粗糙度Ra值为0.075μm,表面粗糙度Rz值为0.579μm。

关键词: 微铣削, 表面粗糙度, 铝合金, 方差分析