NOVEL HEAT DETECTOR FOR EARLY DETECTION OF FIRE BASED ON NiTi SHAPE MEMORY ALLOYS

摘要

Using NiTi shape memory alloys in new type of heat detector allows a unique autonomous detection of fire at its early stage and also provides an opportunity to actuate various fire suppression systems. NiTI alloys were heat-treated to provide rated activation temperatures of 55°C±5°C, 80°C±5°C, 93°C±5°C, 110°C±5°C. The morphology of prepared NiTi samples were characterized by energy-dispersive X-ray diffraction (EDX) and scanning electron microscopy (SEM) techniques. The resulting NiTi alloys were used as a heat-sensitive element in new type of heat detector. The study reveled that high sensitivity combined with actuation function provides a unique opportunity for early fire detection at maximum relative humidity of 98%. The detector is capable of sustaining impacts of up to 4g-force of 2 to 50 milliseconds duration. It is also capable of sustaining vibration from 0.5 to 200 Hz with acceleration of 4g. The reliability investigation of the heat detection based on NiTi shape memory alloys is now in progress.