Silicon Nitride Tubes, Si3N4 Tube

Product Information

Silicon Nitride (Si3N4) has the most versatile combination of mechanical, thermal, and electrical properties of any technical ceramic material. It is a high performance technical ceramic that is extremely hard and has exceptional thermal shock and impact resistance. It surpasses most metals high temperature capabilities and has a superior combination of creep and oxidation resistance. Additionally, its low thermal conductivity and high wear resistance make it an excellent material that can withstand the toughest of conditions in the most demanding industrial applications. Silicon Nitride is an excellent choice when high-temperature and high-load abilities are needed. Silicon nitride ceramic is an inorganic material ceramic that does not shrink during sintering. There are five different methods to produce Silicon Nitride including SRBSN, GPSN, HPSN, HIP-SN and RBSN, make the application and working material different slightly. In these 5 methods of production, GPSN is most commonly used to produce Si3N4 components. The strength of silicon nitride, especially hot-pressed silicon nitride, is one of the hardest substances in the world.

The strength of silicon nitride, especially hot-pressed silicon nitride, is one of the hardest substances in the world. Si3N4 tube is a covalent bond compound with high strength, low density, and high temperature resistance. Due to the even performance in high temperature, Silicon Nitride Tube is a commonly used ceramic material in the metallurgical industry. Silicon Nitride Tube has excellent thermal shock resistance due to the microstructure. The creep and oxidation resistance of Si3N4 is also superior, its low thermal conductivity and high wear resistance also make it an outstanding material that can withstand conditions of most industrial applications.

Synonyms

Trisilicon tetranitride; Nierite

Silicon Nitride Tubes Specification

Dimensions

Per your request or drawing

We can customized as required

Properties（Theoretical）

Gas Over-Pressure Sintered

Hot Pressed

Hot Isostatic Pressed

Silicon Nitride Tubes Advantages

• High strength over a large temperature range

• High fracture toughness

• Good flexural strength

• Mechanical fatigue & creep resistant

• Lightweight – Low density

• High hardness and wear resistance, both impingement and frictional modes

• Superior thermal shock resistance

• Low thermal expansion

• Electrical insulator

• Good oxidation resistance

• Good chemical corrosion resistance

• Wear resistant

• High stiffness

Silicon Nitride Machining

Silicon Nitride can be machined in green, biscuit, or fully dense states. It can be machined relatively easily into complex geometries while in the green or biscuit form. However, the sintering process that is required to fully densify the material causes the body to shrink approximately 20%. This shrinkage means that it is impossible to hold very tight tolerances when machining pre-sintering. In order to achieve very tight tolerances, fully sintered material must be machined/ground with diamond tools. This processes uses a very precise diamond coated tool/wheel to abrade away the material until the desired form is created. This can be a time-consuming and costly process due to the inherent toughness and hardness of the material.

Applications of Silicon Nitride Tubes

• Rotating ball bearings & rollers bearings

 -Bearing technology in automotive engineering

 -Valves, turbocharger rotors for engines

 -Diesel engine glow plugs

• Cutting tools

• Engine components: valves, rocker arm pads, seal faces

 -Seal Rings

• Induction heating coil supports

• Turbine blades, vanes, buckets

• Welding & brazing jigs -Welding Rollers

• Heating Element components

• Crucibles

• Metal tube forming rolls and dies

 -Molten metal handling

• TIG / Plasma welding nozzles

• Weld positioners

• Precision shafts and axles in high wear environments

• Thermocouple sheaths & tubes

• Semiconductor Process Equipment

 -Nozzles

 -Thermocouple sheaths

 -Centering Pins

 -Drawing Tools

 -High-performance Cutting Tools

 -Indexable Inserts

 -Tubes and Pipes

 -Mechanical Engineering Special Applications

Silicon nitride tubes can also be used as protection for thermocouples. Protection Tubes for Thermocouples made by Si3N4 have excellent corrosion resistance and high-temperature strength and can be used in garbage incinerators and melting furnaces with increased operating temperatures. A silicon nitride thermocouple protection tube is used to protect the thermocouple that measures the temperature of aluminum and titanium liquid. Features: -It does not corrode with the aluminum liquid, and the surface does not adhere to the aluminum liquid, which is more conducive to the improvement of the quality of aluminum products; -Strong oxidation resistance, can be used in the air for a long time below 1000 degrees Celsius, without oxidation; -100% dense, aluminum liquid cannot be immersed, silicon nitride produced by the reaction sintering process has a short service life, there are many pores in the material, and long-term aluminum liquid will infiltrate; -Strong thermal shock resistance -At least the service life in the aluminum industry is 6 months, with actual test is more than 1 year.

Packing of Silicon Nitride Tubes

Standard Packing:

Sealed bags in carton boxes. Special package is available on request.

As a ceramic material, Si3N4 is quite fragile in a lot of cases. The Si3N4 Tubes are usually held in plastic bags by vacuum, and protected with heavy foam.

ATTs’ Si3N4 Tubes is carefully handled to minimize damage during storage and transportation and to preserve the quality of our products in their original condition.

Chemical Identifiers