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Micro milling is a machining method of high precision and efficiency for micro components and features. In order to study the surface quality of single crystal materials in micro milling, the two-edged cemented carbide tool milling cutter with 0.4 mm diameter was used, and the orthogonal experiment was completed on the micro-milling of single crystal aluminum material. Through the analysis of statistical results, the primary and secondary factor which impacting on surface quality were found as follows: spindle speed, feed rate, milling depth. The ideal combination of optimized process parameters were obtained, when the spindle speed was 36000 r/min, the milling depth was 10 μm, the feed rate was 80 μm/s, which made the milling surface roughness is 0.782 μm and minimal. Single crystal materials removal mechanism were revealed, and the influence of cutting parameters on micro-milling surface were discussed, the reason of tool wear was analyzed. Those provide a certain theoretical and experimental basis for micro milling of single crystal materials.

In order to improve the surface grinding quality of high volume fraction aluminum matrix composites, the cutting tool models with different rake angles are established, the grinding process is simulated, and the material removal mechanism and the broken state of SiC particles are obtained. Through single factor experiment, the 60% volume fraction SiCp/Al2024 composites are ground by diamond grinding rod with 3mm diameter, the surface roughness (Ra) is measured, and the surface and sub-surface quality of SiCp/Al2024 composites with meso-scale grinding is investigated. Meanwhile, the influence mechanism of grinding depth (ap) on surface quality is put forward, and the influence of different grinding depth on the fragmentation of SiC particles in sub-surface layer is discussed, which verifies the correctness of grinding simulation. The relevant research and theoretical model are of great significance to the study of grinding properties of composite materials.

In this paper, the finite element cutting simulation model with irregular distribution of multiple particles is established, the stress and strain distribution of SiC particles in the process of machining, as well as the material removal mechanism are analyzed. The effects of cutting velocity and feed per tooth on the surface quality of the material are also analyzed. The effect of feed per tooth on subsurface damage is revealed. The results show that in the micro-milling of SiCp/Al2024 composites, the particle removal form is mainly crushing and extraction. The surface defects of the workpiece mainly include pits, scratches, cracks, and extrusion damage. When the cutting velocity increases, the surface defects gradually change to crack, which can improve the surface quality of the workpiece. Increasing the feed per tooth will increase the surface defects of the workpiece and lead to poor surface quality. When the feed per tooth increased from 0.428 µm to 0.714 µm, the subsurface damage thickness increased from 35.2 µm to 47.3 µm.