Quartz piezoelectric ceramic chip
1, the basic principle
The piezoelectric element has a piezoelectric effect and the piezoelectric effect is reversible. The piezoelectric effect is that when some stress is applied to the crystal in a particular direction, the polarization of the crystal is changed, and the amount of change is proportional to stress is called piezoelectric effect, on the contrary, leads to an electric field applied to the crystal strain and the strain of the electric field to proportional to the phenomenon known as the inverse piezoelectric effect. Due to the amount of non-electrical piezoelectric effect, the piezoelectric element can force, pressure, acceleration, temperature, mass and other laws converted into electricity by a certain amount, so it is made available to achieve a certain amount of non-electrical testing, conversion, various sensors such as the role of control and transmission, in military and civilian
The widely used. Is the direct use of the piezoelectric sensor and the inverse piezoelectric effect of the piezoelectric effect is made, or the change in the size of the former is reflected by the piezoelectric charge generated by the piezoelectric element is measured, which is the vibration frequency of the piezoelectric element, or reflect changes in the measured deformation changes.
2 Features
I produced quartz piezoelectric ceramic chip is mainly used sensors, ultrasonic flaw detector, accelerometer, thickness, flow meters, and other areas of production receiving piezoelectric fuze type and emission transducers, dimensions can be produced in diameter Φ3 ~ Φ60 (mm) for any wafer, the ring sheet, tubular, and rectangular sheets can be compared, in addition to common compression vibration mode, shear mode can also be made, the wafer can be divided into the electrode and the gold-plated silver, can be divided into high-temperature burn infiltration, chemical plating and vacuum evaporation, its advanced processing technology, high precision, quality of products in the domestic leading position in the aviation, aerospace, military and other fields has been widely used long-term, praised by users.
3, jargon
A) dielectric constant: dielectric constant known as dielectric constant, dielectric constant or permittivity, it is a factor insulation capability characteristics.
2) electromechanical coupling coefficient: a comprehensive reflection of the piezoelectric coupling mechanical energy and convert between energy levels of the parameter is a measure of the strength of the piezoelectric piezoelectric properties of important physical quantities.
3) The piezoelectric factor: characterization of the piezoelectric material is given by the charge pressure and the degree of conversion to produce a parameter is a measure of the strength of the piezoelectric material of the piezoelectric important physical properties, it is higher, the higher the sensitivity of the piezoelectric material characterization.
4) the Curie temperature: the critical temperature of the piezoelectric body is higher than the Curie temperature, all of the piezoelectric properties would be lost using a piezoelectric material in general about half of the Curie temperature is the temperature.
4, piezoelectric vibration modes of several commonly used
1) long transverse stretching: when the polarization direction of the excitation field and the strips are located along the thickness direction of the particle displacement and wave propagation direction is along the length direction, and thus the transverse stretching.
2) the thickness of the bending-vibration bars: long transverse stretching vibration of the vibrator with the two-ply adhesive, and stick together, and the polarization direction and the direction opposite to the excitation of the electric field, i.e., when the elongation of a deformation, the another piece for shortening deformation, resulting in a composite deformation, the result is a long strip thickness bending vibration, which is packaged piezoelectric sensors and vortex flowmeters and other common modes of vibration.
3) wafer radial diffusion vibration: When the polarization direction and encouragement along the wafer thickness direction of the electric field are, it will produce particle displacement and wave propagation along the radial direction
Expansion vibration.
4) wafer thickness bending vibrations: If two discs radial diffusion oscillator, as long as laminated curved vibrator, polarization and motivation, you can get wafer thickness bending vibration, which is commonly used piezoelectric sensor package vibration mode.
5) thickness shear vibration: If the polarization direction of the piezoelectric ceramic electric field perpendicular to each other and incentives, we can produce the thickness shear vibration, often referred to as cut sheets, which is commonly used in the production of piezoelectric accelerometers and other vibration mode.
5, ordering and precautions
1) When purchasing products, ordering instructions explicitly required product specifications, models and other detailed parameters.
2) Product brittle texture withstand a fall from height in transport or use, violent impact or shock, cause cracking caused by product failure during use should gently.
3) Product electrode easily oxidized to deal sealed storage products, to avoid oxidation electrode affect product performance.
4) Use the temperature can not exceed the specified operating temperature.
