This study investigates high-precision micro-machining of difficult-to-cut materials using polycrystalline diamond (PCD) blade tools. Conventional electroplated blades face limitations in achieving fine grooves due to buckling deformation. To address this, the research focuses on using PCD blades, which offer superior strength and hardness. An electrical discharge machining (EDM) devices was designed and tested to further thin the PCD blades. The EDM process was applied to shape and sharpen the PCD blade edges, resulting in visible discharge marks along the blade periphery. Blade thickness was reduced from 21.6 μm to 18.0 μm through EDM on both sides. The modified PCD blade was then used to machine grooves in PMN-PT piezoelectric crystals. While the blade thickness was 18 μm, the resulting groove width was 25 μm, likely due to blade vibration and misalignment issues. The groove bottom surface roughness was measured at Ra 110 nm, with some grinding marks and micro-cracks observed. The study demonstrates the potential of PCD blades combined with EDM for ultra-fine groove machining, while highlighting areas for further improvement in blade stability and alignment to enhance machining precision.
