Molybdenum alloy pitot probes work well in ultra-high-temperature environments (800°C+) their good creep resistance keeps them dimensionally stable under constant heat.Sensor Calibrationwelcome to click on the website to learn more!
Molybdenum has a high melting point (2620°C) and creep resistance (10x better than Inconel 718 at 1000°C) good for nuclear reactor cooling or plasma wind tunnels. A 1000-hour test at 1000°C showed molybdenum alloy probes had 0.1% creep strain, Inconel 718 had 1% keeping hole alignment and accuracy.
Adding 0.5-1% zirconium and titanium (TZM alloy) stops recrystallization preventing grain growth that weakens high-temp performance. TZM probes in 1200°C furnace kept 80% of room-temp strength, pure molybdenum kept 50%.
But molybdenum oxidizes fast above 600°C in air needs protective coatings (like silicide) or inert gas. A silicide-coated TZM probe lasted 500 hours in air at 1000°C, uncoated one corroded completely after 100 hours.
Machining molybdenum needs carbide tools and slow feed rates (0.05mm/rev) to avoid breaking. A study found using coolant while drilling reduced edge chipping by 70% important for hole precision in high-temp probes.