Sinker EDM and CNC Titanium Machining for High-Precision Aerospace Components

Background: Precision Requirements in Aerospace Components

Aerospace components often require high-precision internal features, tight tolerances, and complex geometries. Conventional titanium machining cannot efficiently create deep cavities, narrow slots, or sharp internal corners without excessive tool wear or distortion.

In this case, sinker EDM titanium machining was integrated with CNC titanium machining to produce high-precision aerospace components. The components required both external profiles and internal cavities with critical dimensions within ±0.01 mm.

Material Selection and EDM Considerations

Titanium alloys were chosen for their high strength-to-weight ratio, corrosion resistance, and fatigue performance. Machining these materials with EDM required careful process control:

• Sinker EDM titanium enabled creation of precise internal features

• Controlled spark energy minimized recast layers and surface defects

• Machinability of titanium alloys influenced electrode selection and machining parameters

This ensured high-accuracy features without compromising material properties.

CNC Titanium Machining of External Features

Before EDM operations, external surfaces and datum references were produced using CNC titanium machining:

• Titanium milling for complex contours and mounting surfaces

• Titanium turning for cylindrical and alignment features

• Drilling and tapping for assembly points

This pre-machining allowed accurate alignment during sinker EDM operations.

Sinker EDM Titanium for Internal Cavities

Sinker EDM was employed to produce:

• Deep internal cavities

• Sharp corner radii

• Narrow slots and blind features

Custom electrodes were designed to match the cavity geometries. Multiple finishing passes ensured minimal recast layers and precise dimensions.

EDM parameters were optimized for spark energy, electrode wear, and flushing efficiency, ensuring high surface integrity and repeatable results.

Integration and Hybrid Machining Strategy

The combination of CNC titanium machining and sinker EDM titanium allowed:

• Accurate external surfaces for reference

• High-precision internal features

• Minimized total machining time

Post-EDM finishing with CNC titanium milling ensured flatness, surface quality, and dimensional compliance.

Dimensional Accuracy and Surface Quality

All critical features were held within ±0.01 mm tolerance. Surface integrity was monitored using metallographic analysis to verify no micro-cracks or structural compromise.

CMM inspection and gauge checks confirmed the high precision of both external and internal features.

Heat Treatment and Stress Management

Selective heat treatment and stress relief were applied to reduce residual stresses introduced during EDM. Solution and aging processes stabilized mechanical properties of the titanium alloys.

OEM Manufacturing and Engineering Support

The project followed an OEM model. Engineering teams collaborated with the customer to:

• Optimize CNC machining sequences for EDM alignment

• Design EDM electrodes

• Plan post-EDM finishing and stress relief

CAD/CAM software such as SolidWorks, UG, and CATIA were used. Supported drawing formats included STEP, DWG, DXF, IGS, STL, and PDF. Prototype components were validated prior to full production.

Applications in Aerospace

Sinker EDM titanium machining combined with CNC titanium machining is widely used in:

• Aerospace tooling and fixtures

• High-precision structural components

• Advanced industrial equipment requiring tight tolerances

This approach enables manufacturers to produce complex machined titanium parts with high reliability.

Conclusion

This case demonstrates how sinker EDM titanium, combined with CNC titanium machining, allows production of high-precision aerospace components. By carefully controlling EDM parameters, electrode design, and post-machining finishing, manufacturers achieve precise, distortion-free internal features and high-quality machined titanium parts.