Product Name: High-Performance Silicon Nitride ($Si_3N_4$) Tube
Product Material: Gas-Pressure Sintered Silicon Nitride (GPSN) or Reaction Sintered Silicon Nitride (RSN).
Material Characteristics: Superior thermal shock resistance (can withstand rapid heating/cooling), Low thermal expansion, Excellent non-wetting properties with non-ferrous molten metals (Aluminum, Zinc, Magnesium), High mechanical strength at high temperatures, Outstanding corrosion and wear resistance, High fracture toughness.
Application Fields: Thermocouple protection tubes, Heater protection tubes, Degassing rotor shafts, Liquid aluminum riser tubes, Molten metal dosing tubes, Industrial furnace radiant tubes, High-temperature gas sensors.
Application Industries: Biomedical (High-temperature sterilization), Advanced Machinery (Molten metal handling), New Energy (Lithium battery calcination), Fluid Control (High-temperature acid delivery), Electronic Engineering (Semiconductor furnace components), Aerospace (Turbine engine sensors), Petrochemical (Heat exchangers), Broad Semiconductor (Wafer processing tubes).
Processing Difficulties: Controlling wall thickness uniformity for extra-long tubes, Managing high sintering shrinkage during the GPSN process, Achieving high-precision thread cutting or flange machining on extremely hard ceramic, Ensuring straightness and concentricity over extended lengths.
Processing Flow: Silicon Nitride powder mixing → Cold Isostatic Pressing (CIP) or Extrusion → Green body machining → Gas Pressure Sintering (1700°C - 1850°C) → Precision diamond grinding (ID/OD) → Dimensional and straightness testing → Dye penetrant inspection for micro-cracks → Packaging.
Delivery Period: Standard protection tubes: 20-35 days, Customized complex large-diameter tubes: 45-65 days.
The Silicon Nitride Tube is the ultimate solution for extreme high-temperature and corrosive environments. Unlike traditional quartz or alumina tubes that may fail under sudden thermal impact, Silicon Nitride maintains its structural integrity even when plunged into molten aluminum. Its unique chemical property of "non-wetting" ensures that molten metal does not stick to the tube, significantly reducing maintenance downtime and contamination. Whether used as a thermocouple protector in foundries or a radiant heater tube in industrial furnaces, our $Si_3N_4$ tubes offer unmatched reliability and service life under the most punishing thermal conditions.
Key Features
Exceptional Thermal Shock Resistance: Can be repeatedly subjected to extreme temperature cycles without cracking.
Non-Wetting to Molten Metals: Ideal for aluminum and zinc casting as it resists metal buildup and dross adhesion.
High Chemical Purity: Inert to most acids and alkalis, ensuring no contamination of the heated medium.
Extreme Mechanical Strength: Maintains high bending strength and hardness even at temperatures exceeding 1000°C.
Extended Service Life: Lasts significantly longer than cast iron or alumina tubes in molten metal applications, lowering replacement costs.
