1、 Material and pretreatment control

1. Stress relief annealing

Before processing, the niobium billet is annealed to release internal residual stress and reduce the risk of subsequent deformation.

2. Surface coating treatment

When processing niobium workpieces with high-temperature protective coatings, the coating should be removed first before processing the welding surface to avoid coating damage and dimensional deviation.

2、 Optimization of processing equipment

1. Selection of high-precision machine tools

Select CNC machine tools with guide rail straightness error ≤ 0.005mm/m and spindle radial runout ≤ 0.001mm to ensure motion accuracy.

2. Special fixture design

Thin walled components use conical self centering fixtures to distribute clamping stress and reduce deformation.

3、 Process parameter control

Cutting processing: speed ≤ 200rpm, trace coolant, hard alloy/diamond cutting tools to reduce tool sticking risk;

Deep hole machining: Ultrasonic assisted technology suppresses tool vibration and improves hole wall smoothness;

Welding surface processing: step-by-step processing: first end face → welding surface → locking bottom structure, cumulative error control within 0.02mm.

4、 Environmental and Testing Management

1. Clean environment

The processing area needs to be dust-proof, and the positioning surface should be cleaned daily to avoid debris causing clamping displacement.

2. Online detection

After the critical process, laser scanning or X-ray inspection is used to correct dimensional deviations in real time.

5、 Residual stress control

Add stress relief annealing after semi precision machining to counteract the newly generated stress during the cutting process.

Application priority: Aerospace thin-walled parts need to focus on fixture design and step-by-step processing; Implants prioritize ensuring surface cleanliness and non-destructive testing.