Free-floating dynamic material removal mechanism of the honing process

Abstract

Honing is an abrasive-based superfinishing process to generate desired dimensional accuracy and functional surface texture. To predict dimensional accuracy of honed components, it is necessary to address and establish an accurate material removal model. However, honing operation differs from other abrasive-based material removal processes such as grinding and polishing in terms of its unique dynamic floating characteristic in the finishing of hole parts such as cylinder bore, adding complexity and difficulty when constructing material removal models. The existing material removal models concerning honing tend to consider the effects of honing trajectory density, pressure, speed and oilstone properties, which are, in essence, the static analysis and ignores the free-floating of honing tools. Therefore, the paper proposed an original honing material removal model based on minimum energy principle to incorporate the effect of free-floating characteristic of honing tool inside hole parts into model. In minimizing constructed objective function 𝐹 𝑜𝑏𝑗𝑒𝑐𝑡𝑖𝑣𝑒 from material removal matrixes of all oilstones distributing on honing head, the model identified the stable spatial position of honing head inside cylinder bore after free-floating, based on which, the material removal matrix corresponding to each oilstone can be identified. Thus, the oilstones' material cutting processes are dynamically connected with each other, overcoming the static and independent analysis for existing researches. To validate the authenticity and credibility of proposed model, the single stage honing 2 / 55 experiment was conducted, and the results showed that simulated inner wall profile after honing using proposed material removal model presented consistency with experimental results in terms of bore diameter enlarging effect and inner wall profile error reflection effect. Furthermore, the simulated results predicted leveling effect for inner wall profile to improve roundness and cylindricity error of cylinder bore, which is the fundamental mechanism of honing but not observed in experiments due to possible exterior errors introduced.