The History and Innovation Behind Zirconia Alumina


Richard M. Sargood, Supervisor Product Engineering, Norton | Saint-Gobain Abrasives

 

Patrick Carroll, Senior Product Manager, MRO, Norton | Saint-Gobain Abrasives

 

John Benkoczy, Senior Product Manager, Norton | Saint-Gobain Abrasives

 

the birth of blue: Zirconia Abrasive Grain History


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key attribute that sets Norton | Saint Gobain Abrasives apart from other abrasive suppliers is its long history of technical innovation as demonstrated by the company’s development and continued improvement of zirconia alumina abrasive grain and products.


In fact, the first patent on fused alumina-zirconia was issued in 1917. Of course, this first zirconia abrasive with only 10% zirconia was a far cry and many generations of innovation from today’s “New Blue” zirconia abrasive grain. The birth of the high-performance “blue” zirconia-alumina abrasive grains occurred in the 1970s with the first patent for these higher performance zirconia grains known as Norzon applied for in 1971.

 

Before zirconia abrasives, the predominant grains were silicon carbide and fused aluminum oxide, which consisted of single crystals. The hardness and wear properties vary in a single crystal. In addition, single crystal fused alumina and silicon carbide grains tend to cleave in large chunks. Flaws or inclusions that are introduced during processing further weaken these grain types. Finer-grained zirconia abrasives have the strength and wear resistance to dig or cut into a surface and then microfracture when stresses become too high in the abrasive.

 

 

In the 1970s and 1980s, Norton researchers invented several additional enhancements to zirconia abrasive, leading to the release of second-generation zirconia coated abrasive products based on the NorZonPlus abrasive grain. In addition to the abrasive grain, several innovations in the adhesive bonding systems and backing were made. These improvements multiplied the benefits of the NorZonPlus abrasive grain to provide enhanced second-generation zirconia coated abrasive products, which were introduced in the 1990s.

 

In 1990, Norton Company was acquired by Saint-Gobain. Saint-Gobain brought to bear a long history and a high level of expertise in processing glass, refractories, furnace design, and ceramic materials. Advances in the fusion or processing of zirconia abrasive grains were an outcome of the new expertise. In the 2000s, third-generation zirconia coated abrasives were introduced based on the NorZonPlus II (NZP II) abrasive grain.

 

Now, in the 2020s, Norton | Saint-Gobain Abrasives is introducing the new BlueFire zirconia coated abrasives based on a fourth-generation zirconia abrasive grain, which combines the latest innovations and optimization of grain shape, fusion processing, and composition. The zirconia-alumina grain composition and shape are finely tuned to enhance resharpening and metal removal rates. While the original “Blue” zirconia grain of the 1970s had a crystal size of 50 microns, the latest generation has a significantly smaller micron crystal size, which provides improved wear properties, superior toughness, and pronounced improvements in resharpening abilities from controlled micro-fracturing.

 

Powerful New BlueFire Zirconia Products from Norton | Saint-Gobain Abrasives

 

While the latest generation zirconia abrasive grain is a key performance factor, the enhancements provided by the New BlueFire zirconia products extend beyond just grain improvements. Innovations in the coated abrasive product design are required to fully exploit the benefits of the new zirconia grain.

 

Since the new abrasive stays sharper longer due to enhanced wear resistance and microfracture resharpening, physics dictates that this will put higher stresses on the adhesive bond and backings. For any applied normal force, the frictional or tangential forces on a disc or belt are higher when the product stays rougher or sharper. To fully utilize the new patented abrasive grain and deliver the best performance possible, the abrasive is coupled with several additional proprietary improvements in backing, bond, and grinding aid systems to maximize cut-rate, material removal, life, and performance.

 

 

The new BlueFire zirconia products utilize a superior re-engineered polyester backing. In addition, the bond system has been improved with tougher, high-stability resins. Finally, an aggressive new grinding aid or supersize formulation is applied for certain applications, which further enhances material removal by reducing heating, sticking or capping, and loading when grinding reactive metals like titanium, magnesium, aluminum, superalloys, high chromium tool steels, and stainless steel.

 

New Blue Rises to Meet the Challenges of Current and New Applications

 

The new BlueFire R887D is a supersized zirconia product designed for grinding stainless steel, titanium, aluminum, superalloys, and magnesium. The new 36 grit BlueFire R887D provides 50% improvement in metal removal compared to the earlier generation zirconia product.

 

The R860 product is the new non-supersized BlueFire zirconia product designed to optimize grinding performance on carbon steels, alloy steels, copper, brass, bronze, fiberglass, and composites.

Sanding composite wind turbine blades is a promising application for the new BlueFire R860 products. Additional industries poised to benefit from the new BlueFire R887D and R860 zirconia coated abrasives include aerospace, automotive, building and construction, plate and structural steel, welding and fabrication shops, and oil and gas.

 

Applications poised to benefit from the new BlueFire R887D and R860 zirconia coated abrasives include:

  • Beveling edges for weld preparation
  • Blending part lines on forgings and castings
  • Flattening weld beads or excessive reinforcement
  • Gate removal and blending on investment castings
  • Heavy stock removal
  • Deflashing molded parts
  • Deburring holes and chamfering edges
  • Surface refinement or finishing

 

The upgraded resin bond and backing system reduces shedding and provides a more durable product even under high-pressure grinding applications. While highly effective at high pressures, the new BlueFire products also increase life and metal removal at low and intermediate pressures.

 

BlueFire R887D is available in belts and quick-change discs. BlueFire R860 is available in flap discs and quick-changes discs. These BlueFire flap discs are available with stiffer T29 conical fiberglass backing plate as well as quick-trim T27 flat plastic backing plate.

 

the consistent quality of BlueFire Zirconia Coated Abrasives

 

While the long history of technical innovations in abrasive grain, fusion technology, and coated abrasive manufacturing are key factors in Norton’s dominance in the field of abrasive products, vertically integrated manufacturing is another factor that positions them as the leader in the abrasives industry. Norton has control of the quality every step of the way, from raw minerals fused into zirconia abrasives to making of the coated abrasive material, to flexing and converting into abrasive discs, belts, and other coated abrasive product forms.

 

Some abrasive suppliers do not manufacture their own abrasive material. Instead, they convert jumbo rolls of coated abrasive material into discs, belts, and other shapes, and since they do not manufacture the products on their own, they do not have the control of quality or understanding of the abrasive technologies (grain, backing, bonding, etc.) required to enhance abrasive life and material removal rate.

 

Even fewer coated and bonded abrasive manufacturers produce their own abrasive grains. Saint-Gobain is the only coated and bonded abrasive manufacturer who produces fused alumina-zirconia, ceramic, engineered abrasives, and silicon carbide, as well as a wide array of other abrasive grains.

 

While the high performance of the new BlueFire zirconia abrasive is a great benefit, quality and consistency in life and metal removal performance are just as important in the manufacturing and fabrication world. Norton | Saint-Gobain Abrasives has the quality and manufacturing systems in place to assure that the BlueFire zirconia products you purchase today will perform as well or better than the BlueFire products you purchase a year from now.

 

New Blue in Your Applications

 

The New BlueFire zirconia abrasive products have the latest generation zirconia grain combined with engineered backings, optimized bonds, and enhanced grinding aids, which result in a product that stays sharper longer and enables grinding at high metal removal rates with long product life.

 

The New Blue and You! What can zirconia abrasives do for your applications?

 

The New BlueFire zirconia coated abrasives are extremely versatile and suitable for grinding and finishing a wide variety of metal alloys including carbon steel, alloy steel, stainless steel, aluminum, titanium, magnesium, cobalt, reactive metals, refractory metals, and nickel-based superalloys. No matter your application, a BlueFire product in the correct product form can be selected to provide enhanced performance. In addition, Norton application engineers can help you optimize the performance of your grinding and finishing operations.

 

Contact Norton | Saint-Gobain Abrasive’s product and application engineers and experts to evaluate the New BlueFire R887D and R860 products and discover the New Blue performance benefits waiting for you in your applications.