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DOE OSTI · 3030562

Physics-guided logistic classification for tool life modeling and process parameter optimization in machining

Abstract

This paper describes a physics-guided logistic classification method for tool life modeling and process parameter optimization in machining. Tool life is modeled using a classification method since the exact tool life cannot be measured in a typical production environment where tool wear can only be directly measured when the tool is replaced. Here, in this study, laboratory tool wear experiments are used to simulate tool wear data normally collected during part production. Two states are defined: tool not worn (class 0) and tool worn (class 1). The non-linear reduction in tool life with cutting speed is modeled by applying a logarithmic transformation to the inputs for the logistic classification model. A method for interpretability of the logistic model coefficients is provided by comparison with the empirical Taylor tool life model. The method is validated using tool wear experiments for milling. Results show that the physics-guided logistic classification method can predict tool life using limited datasets. A method for pre-process optimization of machining parameters using a probabilistic machining cost model is presented. The proposed method offers a robust and practical approach to tool life modeling and process parameter optimization in a production environment.

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BibTeXRIS

Karandikar, Jaydeep, Schmitz, Tony, Smith, Scott. 2021-04-10. Physics-guided logistic classification for tool life modeling and process parameter optimization in machining. https://doi.org/10.1016/j.jmsy.2021.03.025

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