Investigation on self-fabricated PCD cutter and its application in deep-and-narrow micro-grooves

Micro-milling cutter is a critical enabling technology in manufacturing of miniaturized components with sufficient geometrical accuracy and surface integrity, particularly for the high aspect ratio micro-structures. Super-hard diamond micro-milling cutter has exceptional performance compared with conventional cemented carbide micro-milling cutter. However, the preparation of polycrystalline diamond (PCD) micro-milling cutter with large aspect ratio (LAR) is still a major challenge due to its low stiffness, high hardness, and long cutting-edge. In this paper, LAR PCD micro-milling cutter was fabricated through a hybrid approach by combining the pulsed nanosecond laser with precision grinding. Then experimental verifications were carried out on Oxygen-Free Copper material. The machined surface quality, burr formation, and tool wear were investigated through parametric and deep-and-narrow micro-groove experiments. The results confirmed that the self-fabricated PCD cutter could obtain micro-grooves with nano-surface roughness (less than 100 nm), homogeneous bottom surface, and nearly burr-free top surfaces (3 ~ 6 μm). The PCD cutter exhibited high wear resistance and edge sharpness retention in machining of 1.0-mm-depth micro-groove. Furthermore, multi-cycle deep-and-narrow micro-grooves were manufactured by self-fabricated PCD cutter, and the machined quality was proved to be predominant.