A small bore punch die fabricated from YG8 cemented carbide (tungsten carbide) for a precision stamping manufacturer exhibits prominent machining textures and micro-scratches on its inner bore and end faces subsequent to WEDM and sinker EDM processing. The as-machined surface roughness measures roughly Ra 0.6 μm. These surface imperfections readily induce galling and burr formation on stamped components during production, leading to abbreviated die service life and inferior process yield. A high-throughput, consistent polishing process is thus in critical demand.
Polishing cemented carbide via diamond polishing suspension constitutes a highly process-critical operation. Given the exceptional hardness of YG8 cemented carbide, only diamond abrasives possessing greater hardness are capable of delivering efficient stock removal and surface finishing on this substrate.
Defects: Stamped workpieces suffer severe galling and excessive burrs; the die is susceptible to wear and edge chipping.
Post-Polishing Condition
Surface Condition: All scratches are completely eliminated with uniform surface texture. Inner bore edges are intact and free of chipping, delivering a high-gloss mirror finish.
Dimension: Inner bore diameter is stably maintained at approximately 394.6 μm (approx. 0.395 mm) with zero dimensional deviation.
Surface Roughness: Ra value consistently reduced to ≤0.02 μm.
Performance Outcome: Stamped components are free of galling and burrs; surface uniformity of the die is significantly improved.
Product Advantages
✅ Excellent dimensional stability: Only the defective surface layer generated by machining is removed without altering critical die dimensions, satisfying tolerance requirements of precision small-bore punches and other cemented carbide components.
✅ Complete scratch elimination: A staged polishing process optimizes surface quality progressively from rough grinding to mirror finishing, eliminating risks of secondary surface scratches.
✅ Superior surface uniformity: No pitting or edge chipping occurs after polishing; consistent surface finish can be maintained across mass-produced dies.
✅ Broad compatibility: Formulated exclusively for tungsten carbide/cemented carbide, suitable for polishing all types of precision dies post WEDM and sinker EDM machining.
