Tungsten Carbide EDM: Machining Complex Shapes

Introduction

Tungsten carbide can only be processed by diamond grinding or EDM. Electrical discharge machining enables complex shapes that would be impossible with conventional cutting tools.

Wire EDM

Wire EDM cuts carbide with a thin brass or copper wire. It produces precise, intricate profiles with tight tolerances. Wire EDM is ideal for stamping die inserts, extrusion die shapes, and custom geometries.

Sinker EDM

Sinker EDM uses a shaped electrode to burn cavities into carbide. It produces internal features, pockets, and detailed die cavities. Graphite electrodes are commonly used for carbide EDM.

Surface Quality

EDM produces a recast layer on carbide surfaces. For precision applications, this layer is removed by subsequent polishing or lapping. Finer EDM finishes reduce the required polishing time.

Complex Geometries

EDM enables features such as sharp internal corners, thin ribs, and intricate profiles. This freedom allows tool designers to optimize die geometry for performance rather than manufacturing constraints.

Cost and Lead Time

EDM is slower than grinding but enables impossible shapes. For complex carbide tooling, EDM is the only practical option. Programming and electrode preparation are factored into lead time.

Conclusion

EDM machining unlocks the full design potential of tungsten carbide. Complex, precise carbide tooling is now practical for a wide range of applications.

References

GB/T 7714: GUPTA R, SONG J. Powder metallurgy processing and mechanical properties of cemented tungsten carbide composites[J]. International Journal of Refractory Metals and Hard Materials, 2020, 91: 105246.

APA 7th: Gupta, R., & Song, J. (2020). Powder metallurgy processing and mechanical properties of cemented tungsten carbide composites.

MLA 9th: Gupta, R., and J. Song. "Powder Metallurgy Processing and Mechanical Properties of Cemented Tungsten Carbide Composites."