![]() ![]() ![]() As stated by Wan et al. , the gained process understanding in terms of modelling the fundamental machining mechanics can be used for developing force models for more complex machining operations, e.g. This is attributed to the reduced complexity of the process-specific machining kinematics and the associated possibility of a differentiated experimental process analysis. During the last decades, numerous researchers have focussed on developing analytical force models for orthogonal machining of unidirectional (UD) CFRP material. ![]() Accordingly, they help to reduce the tool development time and the number of experimental test series. the influence of varying tool angles or the feed rate on the thrust force, analytical force models represent an important tool for gaining process insights that subsequently can be used for efficient tool or process optimisation. According to Geier and Pereszlai, CFRP components are usually designed and manufactured near-net-shape however, conventional machining operations are usually required for machining difficult-to-mould features, increasing the surface quality or fulfilling other dimensional requirements.Īnalytical force models can be used to estimate the machining forces based on process-, tool- and material-specific influencing parameters. Based on the associated high potential for lightweight construction, CFRP has found increasing application as a high-performance engineering material in commercial aerospace and high-end automotive industries. the cutting edge rounding, the decreasing clearance angle and the increasing contact length at the flank face.Īs exemplarily stated by Davim, carbon fibre reinforced polymer (CFRP) is characterised by high specific strength and stiffness properties, a high corrosion resistance and a low thermal expansion behaviour. Accordingly, the wear model is capable to reproduce the most important wear characteristics, e.g. For model validation, the simulation is compared to experimental data in terms of the cutting edge profiles, the amount of worn tool material and the process forces. Based on an iterative solver, this is used to simulate the tool wear progression during machining. ![]() Using the authors’ previously published analytical force model, the wear rate distribution can be calculated as function of five wear parameters that are used to parameterise the active micro-geometry of an arbitrary wear state. Based on experimental investigation, it is shown that the shape of an arbitrary wear rate distribution between two closely spaced wear states can be approximated and parameterised with a “line - curve - line” approach. For this purpose, a concept called the wear rate distribution is introduced which represents a measure to quantify the wear rate along the active micro-geometry. In this paper, a novel analytical model is presented in order to predict the wear-related change of the micro-geometry in orthogonal machining of CFRP depending on the fibre orientation and the initial tool geometry. Because of occurring wear during machining, the tool’s micro-geometry changes continuously resulting in higher process forces and an increasing risk for workpiece damages. Progressive tool wear due to abrasive carbon fibres is one of the main issues in machining of CFRP and responsible for the short tool life. ![]()
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