Comparison of advantages and disadvantages of ultrasonic transducers

1. Product Categories

Company products can be classified according to different methods.

A. Piezoelectric wafer classification: P4 series with black wafers and P8 series with yellow wafers;

 B. Frequency classification: low frequency series (17~23KHz), intermediate frequency series (25~28KHz), medium and high frequency series (33~60KHz) and high frequency series (68-200KHz);

C. Power classification: 50W series (including 60W), 100W series (including 80W) and other unconventional power;

D. Shape classification: straight cylindrical and horn type;

2 product model selection

In the face of many models of piezoelectric ceramics transducer, it is important to select the appropriate one according to the following instructions.

3.1.Application of different piezoelectric wafer transducers and comparison of piezoelectric wafers:

1). The yellow wafer is a P8 series (according to the national ministry standard) high-power piezoelectric ceramic material, which has the advantages of low heat generation, small field loss and good thermal stability, and is generally suitable for high-power ultrasonic emission. Such as ultrasonic welding, high power cleaning, etc.

2) The black chip is a P4 series piezoelectric ceramic material, which has the advantages of high dielectric constant, high electromechanical coupling coefficient, etc., and is generally suitable for medium power ultrasonic applications, such as cleaning or transceiving sensors.

 3). The black chip used by our company has higher thermal stability, high Curie temperature (Tc=350°C) and high electromechanical quality factor compared with the traditional P4 series.

B. Comparison of different wafer transducers:

1). The yellow wafer assembled ultrasonic transducer vibration cleaning has a low absolute value of capacitance change and a small strong field loss, so that the heat generation is low and the heat is stable with respect to the same driving line. The water flower is characterized by stable change to the cleaning load and large impact, which is a moderately-regular type.

2). The black chip has a high electromechanical coupling coefficient and a high curie temperature, so the electroacoustic conversion efficiency is high. It has higher stability and higher temperature resistance than other products using the P4 series. The water flower is characterized by a high water column and a rich hand feeling, but the sensitivity to the cleaning load is high.

3) Use occasions (recommended): High-frequency (such as 40K or more) or low-power transducer (below 60W) with black chip assembled transducer, low-frequency or high-power transducer with yellow wafer assembled transducer.

2.2. Application of different frequency transducers

The piezoelectric ultrasonic welding transducer frequency is inversely proportional to the wavelength. The wavelength is related to the diameter of the bubble (in a strict sense, it is caused by a low frequency nucleation time), and the bubble diameter is related to its explosion pressure. Generally, the higher the frequency, the smaller is the wavelength, the smaller is the bubble diameter, and the lower the explosion pressure, but the higher is the bubble density and the better is permeability.

Based on the above principles:

1). If the dirt to be cleaned is heavy or difficult to clean, and the impact of the explosion on the surface of the object to be cleaned is not great, the low frequency series transducer should be selected. Commonly used industries in the magnetic industry, auto industry, textile industry, etc. Note that this series is noisy and is best soundproof.

2). If the dirt to be cleaned is slightly heavy or the cleaning is difficult, and the impact of the explosion on the surface of the object to be cleaned is not great, the medium frequency series transducer should be selected. This series of industries is the most widely used, it is mechanical processing industry, electroplating industry, catering industry and so on.