ABSTRACT
 
 

In this study, the behavior of a temperature sensor design for the UDS process is thoroughly studied. The sensor has shown a lot of promise to experimentally measure the transient and spatial temperature behavior of the molten metal droplets.

However, experiments of the temperature sensor inside the UDS system have resulted in failures because of random and unstable behaviors the sensor exhibit when inside the enclosed UDS chamber. Subsequent experiments to test the stability of the sensor in different environments and conditions proved the sensor to be unstable in various conditions. The resistance of the sensor is affected by the amount of current passing through the circuit, at higher currents, the sensor exhibits a lower resistance. When the current running through the circuit exceeds a limit, electro-migration effects may occur which cause permanent changes in sensor resistance. Because of the semi-conductor qualities of the sensing material, the sensor also exhibits photo-sensitive effects which caused change in resistance at the absence of light.

It is still possible to implement the sensor in the UDS system, but the following changes have to be implemented.

• A current divider should be built in the circuit to reduce the current passing through the circuit and prevent electro-migration effects.
• The voltage supplied in the experimental setup will also have to be decreased to a level below 0.2 volts to minimize the effect of change in current on the sensor resistance.
• The sensors will have to be handled very carefully. Grounding at every experimental step is absolutely required to prevent static charge.

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