Views:1 Author:Site Editor Publish Time: 2019-07-26 Origin:Site
What are the parameters that affect the welding effect?
The main welding parameters for ultrasonic welding are: required power, vibration frequency, static pressure and welding time.
(1) Required power Depending on the thickness and hardness of the weldment, it can be determined by:
Where P--power required (W);
K--factor, depending on weldment thickness and hardness, see Figure 2 - 48.
S--weld thickness (mm);
H--weld hardness (HV).
What welding parameters are there for ultrasonic welding? How to choose?
In view of the difficulty in measuring the ultrasonic power, the magnitude of the power is expressed in terms of amplitude, as shown in the following equation:
P=μSFυ = Msf2Aω/π = 4μSFAf
Where P--ultrasonic power (W);
F--static pressure (N);
S--welding area (mm2);
V--relative speed (m/min);
Ω--angular frequency (ω=2πf);
f--Vibration frequency (kHz).
(2) Vibration frequency The ultrasonic resonance frequency depends on the thickness of the weldment and its physical properties. Thin parts should be used with high frequency (up to 80 kHz), and thick parts and materials with lower hardness and yield point should be used at lower frequencies, such as 16-20 kHz. Less than 16 kHz is rarely used due to noise.
(3) Amplitude The power output of the adjustment generator can adjust the amplitude, and the common amplitude is 5-25μm. Due to the large load variation during the welding process, detuning may occur, resulting in reduced joint strength and instability, so maintaining the resonant stability of the acoustic system is the basic guarantee for the quality stability of the solder joint.
(4) Static pressure Static pressure is an important factor that directly affects the power output and the deformation condition of the weldment. The size depends on the thickness and hardness of the weldment. The static pressure at the available power is generally selected and the power is slightly higher than the available power.
Usually to determine the mutual influence of each parameter, you can judge by drawing a critical curve, as shown in Figure 2-49.