Enhanced heat transfer in 3D printed ball-end grinding tool with blade-shaped structure

Abstract

Complex curved components in aero-engines often require demand small-sized compliance ball-end (BE) grinding tools to achieve smooth machining in interference-prone-area. Nevertheless, heat accumulation during the grinding of difficult-to-process materials challenges the weak stability of flexible materials, thereby limited tool life and grinding performance. In this study, a novel rotary-enhanced heat transfer structure (REHT) based on aero-engine blades was introduced into the BE. The blade-shaped structure tools were fabricated using multi jet fusion (MJF). Numerical simulations were conducted to investigate the effects of blade type, rotating direction, rotating speed, and forced cold air velocity on the heat transfer mechanism of BE. The grinding performance of these tools, along with conventional structures, was comparatively investigated through robot-assisted grinding of titanium plates. The results indicated that the REHT improved the heat transfer capability of the tool by introducing high momentum fluids into the tool cavity and increasing the flow rate of the grinding interface. The REHT structure reduced the grinding temperature by over 19.84%, extending tool life by more than 40%. Furthermore, compliant grinding tools with REHT exhibited higher cumulative material removal alongside lower and more consistent surface roughness (Ra).