Pressure Sensor Diaphragm Manufacturing: Etching vs Stamping
Diaphragm Design and Materials
Sensor diaphragm manufacturing requires materials with high elastic limit and low hysteresis. Stainless steel 301 for general use, Hastelloy for chemical environments, titanium for medical sensors. Thickness 0.02-0.5mm.
Thickness tolerance directly affects sensor accuracy. Tighter tolerances (±2μm) enable higher precision pressure measurement.
| Material | Thickness | Max Temp | Use |
|---|---|---|---|
| SS 301 | 0.02-0.5mm | 150°C | General |
| Hastelloy C | 0.03-0.3mm | 300°C | Chemical |
| Titanium | 0.03-0.3mm | 250°C | Medical |
| Inconel 718 | 0.05-0.5mm | 400°C | High temp |
Process Comparison
Chemical etching produces burr-free edges without mechanical stress. Fineblanking offers faster cycle times with ±0.01mm tolerance. Tooling cost: etching $1-3k, stamping $5-15k. Minimum feature: etching 0.1mm, stamping 0.3mm.
Process selection depends on volume, precision and material. Etching preferred for thin foils and complex shapes. Stamping for higher volumes of simpler geometries.
| Parameter | Chemical Etching | Fineblanking |
|---|---|---|
| Tolerance | ±0.02mm | ±0.01mm |
| Edge Quality | Burr-free | Smooth |
| Min Feature | 0.1mm | 0.3mm |
| Tooling Cost | $1-3k | $5-15k |
Quality Verification
Thickness measurement by eddy current at multiple points. Flatness by optical comparator. Pressure cycling for fatigue life. Leak detection for sealed units. Burst test at 3x rated pressure.
Visual inspection for surface defects. Calibration check for sensor output linearity.
