The SiC particle-reinforced aluminum matrix composites are widely employed in different fields due to their outstanding performance. An in-depth understanding of their surface formation mechanism will pave a solid foundation for the widespread application. In this paper, two-dimensional microscale finite element models composed of a SiC particle and Al2024 matrix are established. The effects of cutting speed and tool–particle interaction location on particle behavior and surface formation during micromachining process are investigated. The location is categorized into two scenarios (tool cuts the upper and the lower part of the particle) and different cutting speeds for each scenario are presented. As a result, in scenario one (tool cuts the upper of the particle), the particle fractures by brittle fracture while the depth of surface defects decreases with increase of the cutting speed; in scenario two (tool cuts the lower part), the removal way of the particle changes from being pulled out to being crushed as the speed increases. The von Mises equivalent stresses of the particle and the matrix at the two scenarios are analyzed to explain these phenomena. Experimental measurements of micromilled surfaces are compared with simulation, showing promising results.

SiCp/Al composites are widely used owing to their outstanding performance. However, due to the existence of brittle SiC, surface defects caused by particle fracture damage the surface quality severely. Meanwhile, due to small cutting parameters during the micro-milling process, especially the undeformed chip thickness, which is mainly determined by the feed per tooth, the size effect of matrix also damages the surface quality. In this study, a method by realizing the ductile regime machining of the particle and diverting away the defects of particles and matrix is proposed to select the cutting parameters and improve the surface quality in micro-milling SiCp/Al composites. Suitable range of values of the feed per tooth for side milling and end milling are obtained by this method and validated by micro-experiments. The results show that the size effect of Al and removal ways of the SiC particles affect the machined surface simultaneously. By using suitable feed per tooth, weak size effect of Al and most of the particles’ ductile regime removing can be realized, leading to the generation of the best surface. Additionally, the machining effects of this method are more prominent in end milling than in side milling.

Surface topography is an important characteristic of the surface integrity, and influences the performance and mechanical properties of the workpiece to a great extent in micro milling SiCp/Al composites. It is evaluated by three-dimensional surface roughness ( S_q) and fractal dimension ( D_s) in this paper. Based on the single factor experiment and the orthogonal experiment, the influence of process parameters (feed per tooth, spindle speed, milling depth, and milling width) on surface topography is studied. The results show that S_q is mainly affected by milling width and milling depth and optimal results for minimum S_q are: a_e = 1.5 mm, a_p = 0.08 mm, n = 12000 r/min, and f_z=1 μm/z. While D_s is mainly affected by milling width and optimal parameters for maximum D_s are: a_e=1 mm, n = 14000 r/min, f_z = 1.5 μm/z and a_p = 0.12 mm. There is a weak negative correlation between S_q and D_s. In addition, D_s is more sensitive to the main defects and in general a large D_s corresponds to a good surface.

In micromilling the silicon carbide particle–reinforced aluminum matrix composites, cutting forces can provide a better insight of the cutting mechanism. In this article, an analytical model for force prediction in micromilling composites is developed considering the size effect of the matrix. In modeling, for the matrix, the cutting area is divided into shearing area and plowing area and the removal forces are established considering chip formation and edge forces; for the particle, the removal forces are established based on Griffith fracture theory. The model is verified by micromilling experiments. The influences of the process parameters (milling width, milling depth, and feed per tooth) on the milling force were studied. It shows that the maximum milling force increased with the increase in the feed per tooth and the milling depth and increases first and then stabilizes with the increase in milling width; the average milling force increases with the increase in the three parameters. In addition, the contribution of the particle fracture force is analyzed, and it is found that the contribution of the particle fracture force is affected by the feed per tooth, which basically accounts for about 23% of the maximum milling force and accounts for 23%–30% of the average milling force.

While ensuring thermal safety is critically required in the operation of the composite energetic material, the cutting temperature is a crucial parameter that must be investigated and controlled in its cutting process to avoid thermal explosion. In this paper, we elucidate the mechanisms of heat generation and conduction during the cutting process of a composite energetic material by establishing a microstructure-based finite element (FE) simulation model considering thermal effects. Specifically, we simulated the cutting process of the composite energetic material by FE simulations, with a focus on the variations in the cutting force, the initiation and conduction of the cutting temperature, and the correlation of the damage behavior of the composite energetic material. Subsequently, we conducted a parametric investigation of the effect of cutting speed on the damage behavior and cutting response of the composite energetic material. This paper provides valuable insights for the exploration of the cutting processes of composite energetic materials.