Drilling of Carbon Fiber‐Reinforced Polymer: A Novel Method for Continuous Monitoring and Real‐Time Prediction of Tool Temperature

ABSTRACT Drilling temperature strongly affects the hole quality of carbon fiber‐reinforced polymer (CFRP). During continuous drilling of CFRP, heat accumulation can result in resin softening, exit damage, and degraded hole‐wall integrity, making accurate tool‐temperature measurement essential. However, existing contact‐based temperature measurement methods still struggle to achieve nondestructive tool‐temperature sensing, and it remains difficult to maintain stable measurement after tool changes. To address this issue, a temperature measurement device was designed, which enables tool‐temperature sensing without damaging the tool structure and supports rapid tool replacement. A temperature monitoring system was developed to simultaneously measure the tool temperature at three locations: the end face, the side face, and the tool‐tip. Continuous drilling tests were carried out at five spindle speeds. Temperature responses, the area‐based exit damage factor Fa, hole wall roughness Ra, and their correlations were analyzed to reveal the effect of heat accumulation on hole quality. A TCN‐BiGRU‐Attention model was then developed to predict tool‐tip temperature based on end‐face temperature, side‐face temperature, and time features. The proposed method supports thermal‐state‐based evaluation of exit damage and hole wall roughness in CFRP continuous drilling, with potential applications in aerospace, automotive, and rail transit.