Study On The Tool Wear Mechanism And Tool Life For High-Speed Milling Aeronautic Aluminium Alloy

High speed machining (HSM) is one of the advanced manufacturing technologies and is going mainstream because of its many advantages. However, the short tool life is one of the great obstacles in the application of HSM because of severe cutting conditions. As failure mechanisms of cutting tools in HSM is different with those in conventional machining, new theory and research method should be presented. Although HSM was firstly used in Aeronautics & Astronautics industry, there are still many problems in tool failure especially in high speed machining monolithic parts. Tool failure mechanism and tool life have been studied in high speed milling of aluminum alloy 7050-T7451.High speed machining process plays an important role in tool failure. The appropriate selection and proper use of cutting tools have been researched as well as the determination of resonance regions in high speed milling of aluminum alloy. A new and maneuverable method to determine the resonance regions has been presented according to the fact that vibration will result in the increase of cutting forces and roughness of machined workpiece. With this method, just a single factor experiment should be conducted in which cutting speed is variable. Experimental result is consistent with theoretical analysis.Research on mechanism of cutting deformation is the basis to study cutting force, cutting temperature and tool wear. The degree of deformation, chip formation and shear angle theory have been studied. It is pointed that high strain, high strain rate and high temperature are the main characteristics of high speed machining process. It is found that the intense distort of sliding lines indicates the existing of adhesion wear. The chip patterns have been observed by experiments in high speed turning and milling respectively.Milling forces in high speed milling of aluminum alloy 7050-T7451 have been researched by theoretical analysis and experimental approaches with coated solid cemented carbide cutting tool and uncoated superfine grain cemented carbide inserts. Geometry modeling of radius end milling cutting tool is established by seven-parameter method presented by Altintas. The cutting force models of above two kinds of cutting tools have been established. Also the empirical formulae have been...