Monthly Archives: January 2013

Abrasive Grade Silicon Carbide – Uses Of

Silicon Carbide Grit

Silicon Carbide Grit & Powder

The main uses for abrasive grade Silicon Carbides (Carborundum) are:

Due to the very hard structure of silicon carbide (silicon + carbon) , it has historically been used as an abrasive.  Today, there are many high tech uses for varying grades of Silicon Carbide such as electronics, brake pads, ceramics, LED’s, diodes, transistors, semiconductive research, heating elements, even jewelry.  Gone are the days when Silicon Carbide was known only as an abrasive.

How Is It Made?  Silicon carbide is  manufactured by mixing silica sand (SiO2) and finely ground coke (carbon) together, then they are put into a brick lined electric furnace and baked at high temperature, while at the same time, an electric current is passed through a conductor.  This process can take days from start to finish, with the end result being chunks of silicon carbide of varying purity.   The aggregate is then sorted, crushed, and graded.


Silicon Carbide – Historical Facts

Black Silicon Carbide Abrasive

Silicon Carbide Sandblasting Abrasive

Silicon Carbide (SiC) was the first synthetic abrasive to be produced and also the first to be commercialized.  1891 was the year that silicon carbide production began, and thus revolutionized the abrasive industry as a whole.  Before 1891, almost all abrasives were naturally found such as rocks and minerals.

By 1900 Silicon Carbide production was at 1,200 metric tons, carrying an estimated value of $263,000.  Mainly used in the lapidary industries, it was a replacement for diamond powder.  At that time, the only other manufactured abrasive was crushed steel and as a contrast in volume, crushed steel production was only 320 tons, carrying a rather paltry value of ~$50,000.

With exception only given to diamond and garnet, by the year 2000, manufactured abrasives dominated the high end abrasive industries.  Unlike natural abrasives, manufactured abrasives could be tightly controlled, thus ensuring uniform properties like hardness and grit size.  A further benefit was the ability to customize the manufacturing process to meet exact specified needs, based on the end application.  While being more expensive that natural abrasives, their durability and efficiency made them more cost effective overall.  They are therefore used heavily in the metal finishing, cutting, and polishing fields.

In short, manufactured abrasives are extensively used today in finishing numerous products.