Effects of the granite forming minerals on the surface roughness in the milling processes

Six lines were formed on the surface of each granite specimen by milling. Milling was done by the same machine (Prussiani Golden Plus), with the same parameters (1 mm cutting depth, 40 mm cutting width and 0,1 mm/min feedrate), with the same tools (60 mm diameter, milling tool with 8 segments). While numerous parameters are constant, the rotational speed of spindle was changed and the cutting speed was calculated (37,7 m/min, 75,4 m/min, 113,1 m/min, 150,8 m/min, 188,5 m/min, 226,2 m/min) based on this rotational speed.
The area-based average surface roughness of the minerals was measured in the granite. These component minerals were quartz, mica and feldspar. Quartz, albite and biotite were constant components in each sample. However, in the first two specimens, orthoclase and mica were observed along with albite. For exact surface roughness, measurements were made at the beginning, middle and end of the line.
The surfaces of the samples were cleaned with high pressure air. Then the specimens were put under an Alicona InfiniteFocus IFM G4 confocal microscope. InfiniteFocus is a fast and flexible optical 3D surface measurement system.
During the study, the focus was set to include the roughness peaks and roughness valleys. If the focus is poor, the surface roughness cannot be evaluated. Precise measurement is also supported by the precise movement of the InfiniteFocus object-slide.
The surface roughness of the selected minerals was calculated by the evaluation software of the microscope. During the experiment, area-based roughness was measured instead of line-based roughness to obtain more accurate results.
So, it can be stated that the order of the effect of minerals on surface roughness is the same at all cutting speeds and every particle size.
The results may be greatly influenced by the microhardness of the minerals, their different orientation, and the percentage composition of the sample.

每块花岗岩试样的表面均通过铣削加工出六条刻线。铣削工序均采用同一台设备（Prussiani Golden Plus），并保持一致的加工参数：切削深度1mm、切削宽度40mm、进给速率0.1mm/min，同时使用相同的刀具：直径60mm、带有8个刀齿的铣刀。尽管其余多项参数均保持恒定，但主轴转速有所调整，并据此计算得到切削速度：37.7m/min、75.4m/min、113.1m/min、150.8m/min、188.5m/min、226.2m/min。
本次实验针对花岗岩中的矿物组分测量了基于面积的平均表面粗糙度，所涉矿物包括石英、云母与长石。所有试样均固定包含石英、钠长石与黑云母；而前两块试样中，除钠长石外还含有正长石与云母。为获取精准的表面粗糙度数据，分别在每条刻线的起始、中段与末尾位置进行了测量。
首先使用高压空气清理试样表面，随后将试样放置于Alicona InfiniteFocus IFM G4共聚焦显微镜下进行观测。InfiniteFocus是一款快速灵活的光学三维表面测量系统。
实验过程中，对焦范围设置为覆盖粗糙度峰与谷。若对焦效果不佳，则无法完成表面粗糙度的评估。InfiniteFocus的载物台精准移动功能也为高精度测量提供了支撑。
通过显微镜自带的评估软件计算所选矿物的表面粗糙度。本次实验采用基于面积的粗糙度测量方式，而非基于线的粗糙度测量，以获取更为精准的实验结果。
由此可以得出结论：在所有切削速度与所有粒径条件下，不同矿物对表面粗糙度的影响排序保持一致。
实验结果或受矿物显微硬度、矿物取向差异以及试样组分占比的显著影响。