Tool wear analysis of high-speed sawing of aerospace aluminum alloy based on FEM simulation and cutting experiments

Abstract

As a highly efficient tool, carbide circular saw blades are ideal for hard metal machining, but they face limitations for tooth wear and manufacturing. The study comprehensively analyzes sawing performance and tool wear mechanisms of circular saw blades in the 7075 aluminum alloy sawing process. Firstly, a mathematical model of the instantaneous undeformed chip thickness (IUCT) was developed, and sawing force models were established to explain the vibration characteristics of tools. Moreover, simulation analysis of the aluminum alloy machining process was performed by the finite element method (FEM), indicating that the sawing force decreases and the surface quality is better as the rotational speed increases. However, more heat is generated due to the high-speed friction between teeth and the machined surface. Then, sawing forces and vibration behavior of circular saw blades were studied. Experimental evidence indicates that the substrate's vibration and sawing forces increase with feed rates and sawing depths. In the axial direction, circular saw blades are the least stiff, which tends to cause severe vibration, and the sawing depth is particularly sensitive to tool vibration. A detailed account of the wear characteristics of the teeth is concluded, with the adhesion caused by the sawing heat by scanning electron microscopy (SEM) and electron dispersive spectroscopy (EDS). It was established that adhesion due to sawing heat is the dominant cause of carbide tooth wear. Adhesive wear and misaligned sawing result in scratches and laminations on the surface of the workpiece. The research systematically analyzes the wear characteristics and machining performance of teeth and provides theoretical guidance for designing saw teeth and optimizing machining parameters.