Why can silicon carbide grinding discs become the core consumables for precision machining of hard and brittle materials?- Trojan (Suzhou) material technology Co., Ltd.

Why can silicon carbide grinding discs become the core consumables for precision machining of hard and brittle materials?

08-05-2025

In high-end manufacturing fields such as semiconductors, photovoltaics, and precision ceramics, silicon carbide grinding discs have become indispensable consumables in the precision machining of hard and brittle materials due to their unique physical and chemical properties. Its core advantages come from the high hardness, high thermal conductivity and wear resistance of silicon carbide materials, which make it show significant advantages in processing superhard materials such as silicon carbide substrates, optical glass, and ceramics.

As a representative of the third generation of semiconductor materials, silicon carbide (SiC) has a crystal structure that gives the material extremely high hardness (Mohs hardness 9.2-9.5) and wear resistance. In high temperature environments, silicon carbide's anti-oxidation properties are particularly outstanding: when the temperature rises to 1300°C, a dense silicon dioxide protective layer is formed on the surface, which enables it to maintain stability during high-temperature processing.

The manufacturing process of silicon carbide grinding discs needs to take into account both material properties and processing requirements. Its core processes include:
Raw material ratio: high-purity silicon carbide micropowder (particle size range 0.5-30μm) as the main material, with resin, ceramic or metal binder, supplemented by plasticizer, lubricant and other additives.
Molding process: through hot pressing or injection molding technology, ensure the compact structure of the grinding disc and uniform particle distribution.
Sintering and curing: sintering at a high temperature of 1800-2200℃, so that the binder and silicon carbide particles form a firm bond, while controlling grain growth to avoid increased brittleness.
This process system ensures that the grinding disc has sufficient toughness to resist processing impact while maintaining high hardness.

The core advantage of silicon carbide grinding disc in hard and brittle material processing
Silicon carbide grinding discs show significant advantages in processing silicon carbide substrates. Traditional aluminum oxide abrasives are prone to passivation of abrasive particles due to insufficient hardness during processing, while silicon carbide grinding discs can achieve more efficient material removal rates due to their higher hardness. For example, in the thinning process of 8-inch silicon carbide wafers, the monolithic processing method of silicon carbide thinning grinding wheels can achieve sub-micron surface accuracy, which is significantly better than traditional grinding processes.

The high thermal conductivity of silicon carbide (300-490 W/(m·K)) gives it a natural heat dissipation advantage in high-speed processing. In the photovoltaic silicon wafer cutting scenario, diamond wire saws combined with silicon carbide abrasives can effectively reduce cutting temperatures and avoid crack propagation caused by thermal damage. This feature is particularly important when processing materials with poor thermal conductivity such as alumina ceramics and silicon nitride.

The wear resistance of silicon carbide grinding discs extends their service life by 3-5 times that of traditional abrasives. In the processing of ceramic bearing rings, a single silicon carbide grinding wheel can continuously process more than 2,000 workpieces, while an alumina grinding wheel can usually only maintain a processing volume of 500-800 workpieces. Although the initial cost of silicon carbide grinding discs is high, their comprehensive use cost can be reduced by more than 40%.

In the production of silicon carbide power devices, substrate processing is a key link in determining device performance. Silicon carbide grinding discs achieve high-precision processing through the following technical paths:
Double-sided grinding process: Using silicon carbide grinding discs with polyurethane polishing pads can achieve substrate thickness uniformity of <1μm processing accuracy.
Chemical mechanical polishing (CMP): The polishing liquid based on silicon carbide abrasives can effectively remove the surface damage layer of the wafer and reduce the surface roughness to below 0.2nm.

In the ultra-precision processing of optical glass, sapphire and other materials, silicon carbide grinding discs achieve the following through micro-nano-scale particle size control:
Mirror processing with surface roughness Ra <0.5nm
Microstructure molding with subsurface damage layer depth <5nm
This performance is irreplaceable in the manufacturing of high value-added optical components such as laser crystals and infrared windows.

In response to the processing needs of engineering ceramics such as silicon nitride and zirconium oxide, silicon carbide grinding discs achieve the following by optimizing the abrasive grain morphology and grading:
Processing efficiency increased by more than 60%
No microcracks remain on the processed surface
This breakthrough has promoted the performance upgrade of products such as ceramic bearings and ceramic cutting tools.