A micro-cutting constitutive model based on grain boundary hardening effect

doi:10.13251/j.issn.0254-6051.2020.11.048

Abstract

Abstract: A micro-cutting constitutive model containing average grain size of the material was established by considering transgranular boundary cutting and cutting flutter at the fine grain level, and based on the Hall-Petch relation relating to the grain boundary hardening effect as well as the conventional metal cutting constitutive model. The coefficients of the model were corrected by simulation and cutting force experiments. The results show that the grain boundary strengthening effect is more obvious when the average grain size is 0.07-0.20 mm. When the average grain size exceeds 0.20 mm, the predicted trend of micro-cutting constitutive model for cutting force gradually approaches that of the conventional metal cutting constitutive model. And as the average grain size increases, the prediction difference between the conventional metal cutting constitutive model and the proposed micro-cutting constitutive model decreases gradually. Comparison of experimental data with theoretical data verifies the accuracy of the micro-cutting constitutive model.

Key words: grain boundary hardening, micro-cutting, constitutive model, average grain size

CLC Number:

TG166

Wang Minting, Shen Lixiong, Cao Mingfei, Zhao Lei, Li Zhe. A micro-cutting constitutive model based on grain boundary hardening effect[J]. Heat Treatment of Metals, 2020, 45(11): 248-254.

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