Achieving precise chip control for high-end manufacturing

In high-end manufacturing, where precision and automation are strictly required, chip control presents an incredibly daunting challenge during the machining process. In this paper, a novel chip control method called grooves induced chip-breaking (GICB) is comprehensively investigated. The core concept of GICB is to achieve spontaneous chip-breaking through the pre-processed micro grooves (PPMG) on the workpiece surface. To understand the underlying chip-breaking mechanisms, PPMG with identical geometric shapes are fabricated on the surface of a 316 L stainless steel workpiece using laser ablation. A cutting experiment is then conducted, where the cutting depth (d) and feed rate (f) are varied. Experimental observations reveal that, apart from enabling controllable chip-breaking, the GICB method can also enhance the quality of the machined surface. Specifically, the surface roughness (Ra) is reduced by up to 26.6%. Further in-depth analyses indicate that the primary cause of this improvement is the reduced fluctuation of the thrust force. With the assistance of PPMG, the chips produced under controlled periodic fracture exhibit similar lengths and curvatures. Benefiting from that, chip agglomeration and entanglement are effectively avoided. In addition, the fluctuation of cutting force is greatly reduced, which in turn improves the machined surface quality. The practical significance of this study is twofold. Firstly, a high-performance chip control method with significant potential applications is systematically explored. Secondly, for the first time, the crucial relationship between chip control and machined surface quality is experimentally verified.