Flow dynamics in the micro-sized channel and chamfer formation mechanism during abrasive flow machining

Chamfering at the orifices of micro-sized channels plays a critical role in controlling flow dynamics and extending the service life of pipelines. Abrasive flow machining (AFM) technology is widely used for micro-sized chamfering; however, the underlying mechanism of chamfer formation during AFM remains poorly understood, limiting the parameter optimization of chamfering process. A comprehensive understanding of this process requires elucidating the interaction between flow behavior within micro-sized channels and the chamfer morphology. In this study, numerical simulations are employed to systematically investigate the effects of abrasive flow on channel walls with varying chamfer geometries. Through systematic analysis of flow state evolution, we investigate the variations of shear stress and pressure distribution at chamfered inlets under different polishing conditions. Based on these results, a phenomenological model is proposed. These findings establish a theoretical framework for elucidating chamfer formation mechanisms and provide practical guidance for optimizing AFM parameters in micro-channel chamfering applications.