ACOUSTIC RESONANCE & ULTRASONIC PLASTIC JOINING

Ultrasonic Plastic Welding Horn & Booster Resonance Calculator

Compute half-wavelength acoustic resonant length (L = c / 2f), acoustic amplification gain (G), nodal clamping plane location, and triangular energy director joint geometry.

1. Acoustic System Inputs

2. Resonant Dimensions & Energy Director

Resonant Length (L)
0.0 mm
Acoustic Gain (G)
1.00×
Nodal Plane (Z_node)
0.0 mm
Energy Director Height
0.0 mm

3. Standing Wave Amplitude Visualizer

Ultrasonic Tooling & Joint Prepress Notes

1. Half-Wave Resonance Principle: The physical length of an acoustic sonotrode must match an exact integer multiple of half acoustic wavelengths: $L = \frac{c}{2f}$. Nodal mounting rings must be located exactly at the zero-displacement / maximum-stress plane ($Z = L/2$).

2. 60° Triangular Energy Director: For amorphous polymers (ABS, PC, PS, PMMA), standard energy directors have a $60^\circ$ apex angle with height $H = 0.5 \times t$ and base width $W = 2 H \tan(30^\circ) = 1.155 H$. For semi-crystalline polymers (PA, POM, PP, PE), shear joints with $0.2 - 0.4\,\text{mm}$ interference are recommended.

3. CNC Turning Splines & Surface Finish: Transitions between input and output diameters must use continuous tangential radius fillets ($R \ge 6.0\,\text{mm}$) polished to $\text{Ra} \le 0.4\,\mu\text{m}$ to eliminate stress concentration and prevent acoustic fatigue fracturing.