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Silicon carbide-reinforced aluminum matrix composites (SiCp/Al) have excellent physical properties, but the presence of SiC particles in the reinforcing phase causes severe tool wear and more serious surface defects during cutting, which seriously hinders the machining efficiency of SiCp/Al composites. To improve the surface quality of SiCp/Al composites and improve the tool wear problem, it were carried out that simulation and experimental verification of the milling tool parameters of SiCp/Al composites and experimental study of CMQL with the selected tool parameters. The results show that the cutting tool with rake angle of 4° and relief angle of 10° can achieve efficient cutting of SiCp/Al composites. The CMQL condition can effectively reduce the surface roughness, improve the surface microstructure, reduce tool wear and increase tool life; The increase of cutting speed can reduce the machined surface roughness, while the increase of feed and cutting depth will lead to the increase of surface roughness. [ABSTRACT FROM AUTHOR]

A strategy developed for obtaining positive cellular responses remains to be focused in the filed of functional biomimetics. In this study, a hydrogel covered simvastatin-loaded polyetheretherketone (PEEK) bio-composites was constructed with the purpose of bone tissue regeneration therapy. Briefly, a three-dimensional (3D) porous structure was fabricated on PEEK surface; then the substrate was functionalized with the poly(L-lactic acid)/simvastatin porous film and hyaluronic acid hydrogel subsequently. In vitro cell attachment, proliferation, and cytoskeletal observation experiments reveal that our scaffolds show better bio-affinity due to the layer of hyaluronic acid hydrogel compared with control. Furthermore, the alkaline phosphatase activity, calcium mineral deposition evaluation, and gene expression for osteogenic potential all exhibit that the superior osteogenic differentiation of MC3T3-E1 pre-osteoblasts on our scaffolds. Therefore, our PEEK samples loaded with simvastatin and covered with hyaluronic acid hydrogel hold great potential in clinical applications for bone repair. [ABSTRACT FROM AUTHOR]