high-temperature thin-film ultrasonic transducer

A wide range of high-temperature thin-film ultrasonic transducer are introduced. high-temperature thin-film strain gauges and high-temperature thin-film strain gauges are used for alloy thin films duo to the sensitive materials at an early stage. Due to different material characteristics and manufacturing processes of ultrasonic distance transducer, thin-film strain gauges are made by different alloys .which can withstand the temperature varies greatly. For example, NiCr alloy thin-film strain gages can withstand test temperatures of 600°C; PdCr alloy thin-film strain gages can reach a maximum operating temperature of ultrasonic distance sensor. 

After optimization of process parameters, they can be used at a temperature of 1 100°C; Ni-CrAlY thin-film strain gages can withstand temperatures up to 800°C. piezo ceramic materials can withstand higher temperatures than alloys at present, piezo ceramic strain gauges include ITO (Indium Tin Oxide) and TaN 2 types. ITO thin-film strain gages can operate at room temperature of ultrasonic range sensor datasheet, but the strain level and temperature have a large effect on the coefficient of variation, which is mainly caused by the diffusion of oxygen in the ITO film. TaN thin-film strain gauges can withstand temperatures up to 400°C. Process parameters have a great influence on the microstructure of TaN thin films ultrasonic range sensor .the coefficient of resistance and strain coefficient of thin-film strain gauges. The TCR temperature coefficient of resistance of piezo ceramics and alloys is opposite to each other and can cancel each other. 

At present, multilayer thin-film strain gauges are made of piezo ceramics and alloys have been produced. TaN is unstable in the air above 500°C, so the using temperature of TaN/PdCr multilayer strain gauges does not exceed 500 °C. The barium strontium titanate is used as the sensitive medium of the capacitive ultrasonic distance measurement sensor, and the PdCr electrode as the high temperature thin film strain gage adopts a flat plate interdigitated structure and can withstand a high temperature of 500°C .