Development of novel guar gum hydrogel based media for abrasive flow machining: Shear-thickening behavior and finishing performance.

• Novelly developed shear-thickening guar gum hydrogel based media for AFM is proposed in this paper. • A new model for the calculation of shear rate under shear-thickening condition is established and validated. • Surface roughness in terms of Ra using this media reduces from 120.12 nm to 6.48 nm, with a mirror surface obtained. • The conclusions show that shear thickening in AFM is an efficient way to develop the polishing efficiency and quality. Abrasive flow machining (AFM) is a non-traditional finishing method by extruding abrasive media through workpieces' surfaces. In AFM process, the machining capacity of traditional shear-thinning media will be reduced with the decline of viscosity at high shear rate condition. Additionally, the environmental-friendly property of traditional oil-soluble media is poor as the recycling of the media is difficult. In this paper, with an attempt to apply shear thickening to AFM, a novel type of guar gum hydrogel based media with shear-thickening property is proposed. To investigate its shear-thickening and finishing performance, a model of identifying the shear-thickening behavior in AFM is established. Results of the validation experiment show that the model can identify and predict the experimental conditions accurately, and the simulation results are approximately some with the model results. Results of AFM experiments show that finely polished surface can be obtained in the AFM process utilizing this new media. Compared with styrene-butadiene rubber based media (traditional shear-thinning media for AFM), guar gum hydrogel based media can obtain a better finished surface under shear-thickening condition. With shear rate increasing from shear-thinning phase to shear-thickening phase, material removal rate for AISI316 stainless steel in the experiment utilizing this new media increases from 69 mg/h to 351 mg/h, and surface roughness in terms of Ra under shear-thickening condition reduces from 120.12 nm to 6.48 nm. [ABSTRACT FROM AUTHOR]