Zirconia ceramic probes excel in ultra-high-temperature environments (up to 1600°C), making them ideal for applications like furnace exhausts and rocket engine plumes, but their brittleness requires targeted mitigation strategies.Sensor Calibrationwelcome to click on the website to learn more!
Zirconia’s key advantage is its stable crystalline structure at high temperatures, unlike alumina which begins to soften above 1500°C. A 1600°C furnace test showed zirconia probes retained dimensional stability for 500 hours, while alumina probes shrank by 0.5% after 300 hours, altering pressure readings.
To address brittleness, adding 3mol% yttria stabilizes zirconia’s phase, reducing thermal shock-induced cracking by 40%. This stabilized zirconia (3YSZ) flexural strength at 1000°C is 200 MPa, double that of pure zirconia. In a thermal cycling test (20°C to 1600°C), 3YSZ probes survived 50 cycles, compared to 10 cycles for pure zirconia.
Design modifications further enhance durability. Rounding all edges (minimum radius 1mm) reduces stress concentration, and a hollow core (30% of diameter) lowers thermal mass, minimizing temperature gradients. A comparison test found hollow 3YSZ probes had 60% fewer cracks than solid ones after rapid heating.
Installation requires shock absorption. Mounting probes in silicone-rubber-lined fixtures dampens vibrations, a critical step in industrial furnace tests where mechanical oscillations can cause catastrophic failure. In one plant, rigidly mounted zirconia probes failed within weeks, while shock-mounted ones lasted 6 months.