Analysis of orthogonal edge trimming of uni-directional composites: numerical, analytical, and experimental approach
As the use of composites increases, more problems arise with processing and manufacturing of this type of material in order to make it a more durable and reliable for today’s applications. One of the most important problems in the cutting of composites is the poor quality of the machined surface and unknown status of the machining forces. Knowing the status of forces during the final machining process helps reduce such defects as delamination and fiber-matrix debonding. This research attempted to develop a fully theoretical model for edge trimming of composites for fiber orientations greater than 90 degrees. The energy method was used as the approach, and the machining forces were compared to the experimental results. A series of experiments were conducted to validate the theoretical foundations. Composite coupons with different fiber orientations and tool rake angles were prepared for the machining experiments, and the cutting forces were measured using a four-component dynamometer. In addition, a finite element model (FEM) was built to model the depth of damage along the fibers. The theoretical depth of damage compared to the FEM analysis showed that they were in good agreement. The parameters affecting the machining forces of composites can be divided into three categories: tool geometry, material properties, and machining conditions. The effect of all of these parameters is reflected in the formula. In addition to the thrust and cutting forces, the depth of damage along the fibers can be calculated. It was concluded that the material properties and machining conditions, more than the geometry of an orthogonal cutting tool, are more influential in affecting the processing and manufacturing of composite materials.