Moscow State Steel and Iron Alloy Institute developed a new vibration sensor
June 21 15:09:14, 2024
[ China Instrument Network Instrument Development ] According to the Russian Science website reported on February 24, researchers at the National Research Institute of Technology Moscow State Steel and Alloys Institute developed a new type of vibration sensor for building and bridge state diagnostic instruments and spacecraft. The sensor uses a lead-free lithium niobate (LiNbO3) crystal. The research results were published in the journal Sensors.
Lithium niobate crystals are much more stable than the zirconium titanate ceramics currently used by vibration sensor manufacturers. The transition to new materials will enable manufacturers to comply with the EU Directive on the gradual ban on lead.
According to Irin Kubasov, a researcher at the School's Department of Semiconductor and Dielectric Materials, vibration sensors can be used in diagnostic equipment for building and bridge conditions to detect any dangerous vibrations in order to act in time to evacuate personnel. They can also be used in spacecraft and security systems to achieve complete control over national territorial boundaries.
The working principle of the vibration sensor is based on the piezoelectric effect - the piezoelectric element deforms and gives an alarm signal when vibration is applied. So far, sensor manufacturers have encountered many problems when using zirconium-titanate lead-based piezoelectric elements, which are extremely toxic and lose sensitivity when temperature changes. Researchers believe that all of these problems are now completely resolved, because lithium niobate does not contain fine particles like zirconium titanate ceramics. In addition, the performance of lithium niobate is stable over a wide temperature range.
Lithium niobate has been known since the mid-20th century and is widely used in laser optics, but few attempts have been made to use it in vibration sensors because its piezoelectric properties are rather weak (about zirconium-titanate lead ceramics). 10 times worse). Experts at the Moscow State Institute of Steel and Alloys have been able to form a so-called "dual-domain structure" inside lithium niobate, which increases their sensitivity to external vibrations. The development of new sensors based on single crystal piezoelectric sensors will increase the sensitivity of these products to at least 10-6 g and also significantly expand the range of operating temperatures.
(Original title: Moscow State Steel and Iron Alloy Institute developed a new type of vibration sensor)
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