Taking The Mystery Out Of Abrasives
Abrasives are not an end, but a means to an end. The customer who buys a drill does not really want a drill, he wants a hole. Similarly, the customer who purchases abrasives does not want abrasives; he desires certain dimensions, certain finishes, or other physical characteristics for his products.
A study of early history reveals the use of natural minerals for the shaping and polishing of objects of art and hand tools. Minerals such as flint, emery, sand, corundum, garnet and diamond found in deposits in various parts of the world were used. Soft sandstone was cut into a wheel shape, mounted on a spindle and was manually operated to sharpen tools. Later in the 19th century, these minerals were bonded to form the first grinding wheels. As the industrial revolution progressed, it was found that natural minerals were not satisfactory for production techniques as natural minerals vary in performance, depending upon the quality level of the deposits from which they are extracted.
Two important events occurred at the beginning of the 20th century which revolutionized grinding and polishing techniques. In 1891, Dr. Edward G. Acheson, in attempting to synthesize diamonds, created a new abrasive – silicon carbide. In 1900, Charles B. Jacobs fused bauxite in an electric arc furnace and formed the first crystals of abrasive grade aluminum oxide.
Aluminum Oxide, a tough, blocky grain and Silicon Carbide, a very hard, sharp grain, and variations thereof are the most common grains used in today’s bonded abrasive products for the grinding and cutting of metal and masonry types of products.
In the next edition of CONNECTIONS, we will continue this series with an article on “Aluminum Oxide – The Work Horse of Bonded Abrasives”.
Catégories: Articles, Articles English