Black silicon carbide

Types of Black Silicon Carbide

Black silicon carbide is a widely used material for making abrasives, due to its hardness and sharp edges. The following are its common grain sizes:

• Finer Grains

  Finer grains range from 60 to 240 mesh. Due to their smooth cutting action, they are suitable for finishing operations. These fine abrasives are used in industries to give a polished finish on hard materials like glass and ceramics.

• Medium Grains

  Medium grains, such as 36 to 60 mesh, are employed for general-purpose grinding and casting of aluminum. They strike an effective balance between removal rate and surface finish. Therefore, they are ideal for heavy-duty tasks, including shaping metals and removing material from workpieces.

• Coarser Grains

  Coarse black silicon carbide grains, ranging from 8 to 36 mesh, are suitable for aggressive grinding and cutting applications. These apply where fast material removal is necessary. They also prepare surfaces for welding or coating. Coarser grains are typically used in metalworking industries to shape hard steel and alloys.

What Are The Industry Applications of Black Silicon Carbide

Black silicon carbide is utilized in various industries to suit different roles. A few of them include:

• Aerospace Industry

  Black silicon carbide is critical in the aerospace industry. This is owing to its role in the manufacture of lightweight, high-strength components. Therefore, it provides superior abrasion resistance.

• Optical Coatings

  The semiconductor industry has fine black silicon carbide powder. They are usually mixed with binders in the optical industry to produce grinding wheels and powder. These enhance the precision shaping of optical components. Thus, ensuring the required clarity and performance of lenses and mirrors.

• Renewable Energy Solutions

  Due to its thermal conductivity and durability traits, black silicon carbide has a key role in energy solutions. It is specifically used in the production of silicon carbide photovoltaic cells to enhance the efficiency of solar panels. Because it is eco-friendly, it is a popular material to produce renewable energy solutions.

• Electronic Components

  The black silicon carbide ceramic is gaining popularity in the electronics industry. This is due to its electrical conductivity. It is ideal for making semiconductor devices and high-speed electronic components. In addition, its temperature resistance makes it suitable for the production of diodes and transistors used in power applications.

• Coated Grains and Slurry Abrasives

  Due to its purity level and high toughness, black silicon carbide is coated on abrasive tools to grind hard materials. Its superior toughness and sharp cutting edges enable it to easily grind and cut hard materials. This makes it suitable for coated grains and slurry abrasives for precision machining and surface finishing.

• Engineered Ceramics

  Due to its hardness and wear resistance, black silicon carbide is also popularly used in producing engineered ceramics.

• Ultra Precision Grinding Wheels

  Black silicon carbide grains are utilized in the production of ultra-precision grinding wheels. These wheels enable ultra-precision machining of hard materials.

What Are The Key Features of Black Silicon Carbide

As a brittle material, black silicon carbide is ideal for precision grinding and cutting. Listed below are its key features:

• Abrasive Properties

  Due to its sharp cutting edges and hardness, black silicon carbide is highly abrasive to give it an edge over other soft carbides. Commonly embedded in coated and bonded abrasives, its high friability (the ability to break into sharp edges when worn) allows it to maintain a cutting edge as it wears down during the grinding process. This makes it ideal for precision grinding.

• Crystal Structure

  Black silicon carbide has a unique hexagonal crystal structure. It gives it its exceptional hardness and sharp cutting edges. While other carbides have a cubic structure, this crystal shape allows it to break into finer, sharper particles during grinding.

• Hardness

  Black silicon carbide’s hardness is ranked 9 on the Mohs scale. This primarily makes it one of the hardest abrasive materials after diamond. It can thus easily grind and cut hard materials like metals, ceramics, glass, and stone.

• Friability

  Since black silicon carbide is friable, it can easily break into sharp edges when worn down. This characteristic allows it to continuously expose new cutting edges during the grinding process. It thus maintains its effectiveness as an abrasive for a long time.

• Thermal Conductivity

  Black silicon carbide has impressive thermal conductivity properties. This enables it to dissipate heat during grinding. It is thus suitable for applications where heat buildup can be detrimental. For instance, in machining metals with low thermal tolerance.

• Chemical Resistance

  Black silicon carbide is chemically inert to most acids and alkalis. This gives it a high level of chemical resistance. Therefore, this makes it suitable for use in hostile environments where other abrasives might deteriorate. This includes applications in chemical processing plants and laboratories.

• Versatility

  Due to its fine and coarse grades, black silicon carbide is suitable for dry and wet grinding. It thus makes it a versatile abrasive. It effectively handles different tasks, from precision finishing to heavy material removal, in various industries like metalworking and aerospace.

How to Choose Black Silicon Carbide

Choosing the correct silicon carbide grain size is essential to ensure optimum performance in different applications. Below are key factors to consider when purchasing it:

• Abrasive Application

  Determine whether a bonded, coated, or non-bonded abrasive will be used. For bonded abrasives, consider the shape, hardness, and strength of the wheel or disc required. For coated abrasives, consider the length, type, and manner in which the abrasive is fastened onto the backing. For non-bonded abrasives, consider the concentration and uniformity of particles in the slurry.

• Abrasive Material

  Black silicon carbide is commonly used for grinding and cutting hard materials. Such include cemented carbide, alloy, and hard metal. White fused alumina is better suited for softer materials. These include soft steel and non-ferrous metals.

• Abrasive Grit Size

  Finer grit sizes (higher mesh numbers) are ideal for special finishes, while coarser grit sizes (lower mesh numbers) are appropriate for removing a lot of material quickly. In the production of grinding wheels, medium grit sizes are commonly used to strike a balance between material removal and achieving a fine finish.

• Abrasive Bond Type

  Bonded abrasives are tougher when using a vitrified bond. Vitrified bonds are particularly ideal for grinding ferrous and non-ferrous metals, as well as hard alloys like tool steel. However, when using a hard bond, such as one made using resin, a flexible and stronger-cutting wheel is obtained, ideal for special and precision finishes.

• Experimental Testing

  After considering the above factors, the next step is to conduct some actual tests to verify the hypothesis. This may take time, especially when dealing with several variables. However, it is worth it in the end.

Q&A

Q1. What is black silicon carbide made of?

A1. Black silicon carbide is made by mixing silica (silicon dioxide) and petroleum coke (or other carbon sources) in an electric arc furnace to create silicon, which bonds with carbon to form silicon carbide. It is heated to 2500°C to form silicon carbide crystals, which are then crushed into various grain sizes. The resulting black silicon carbide powder is commonly used as an abrasive.

Q2. What is the difference between green and black silicon carbide?

A2. The primary difference between green and black silicon carbide is their source and purity. Green silicon carbide is purer, tougher, and harder than black silicon carbide. It is ideal for precision grinding hard materials. On the other hand, black silicon carbide has lower purity due to impurities like iron and silica. It is ideal for abrasive applications due to its effective sharp edges.

Q3. What is silicon carbide abrasive paper used for?

A3. Silicon carbide abrasive paper is used for smoothing, sanding, and finishing, especially on hard surfaces like metal, glass, wood, and ceramics. Its silicon carbide grains provide a sharp, long-lasting edge for effective material removal, whether used dry or wet. It is especially ideal for wet sanding to reduce dust and improve surface finish.

Q4. Is silicon carbide the same as carborundum?

A4. Yes, silicon carbide and carborundum are the same. Carborundum is merely a tradename for silicon carbide. Silicon carbide is commonly used in abrasives, cutting tools, and refractory materials for their hardness and heat resistance. It is also used in manufacturing semiconductor devices.