Silicon nitride is widely used in high-performance engineering applications due to its exceptional thermal, mechanical, and chemical stability. It is a key material in manufacturing ceramic bearings and bearing balls, especially for high-speed and high-temperature environments where steel bearings would fail. Its low thermal expansion and high fracture toughness make it ideal for use in automotive and aerospace components such as turbocharger rotors, glow plugs, and heat engine parts.

In the electronics industry, silicon nitride serves as a passivation and insulating layer in integrated circuits, protecting devices from moisture and mechanical damage. It is also used as a mask in diffusion processes during semiconductor fabrication.

Due to its excellent wear and corrosion resistance, silicon nitride is employed in cutting tools for machining hard metals, significantly increasing tool life and performance. Additionally, it is used in medical applications, such as spinal implants, where its biocompatibility and durability support long-term structural function.

In the metal processing industry, silicon nitride is used to manufacture tubes, crucibles, and other components that come into contact with molten metals such as aluminum, due to its non-reactivity with molten metals and long service life.

In advanced technologies, silicon nitride is finding use in laser systems and photonic devices, particularly in waveguides and resonators, thanks to its high refractive index and low optical loss in the visible and near-infrared range.