August 08, 2019

Abrasive Polishing with Engineered Grains

Abrasive polishing is both an innovative and an age-old technique used to alter the topography of a surface to achieve a desired finish. As early as 12,000 BCE, mankind used crushed crustacean shells, pumice stones, and quartz sand to polish tools and decorative figurines . Quartz is still used in abrasive polishing today, owing to its ubiquity on earth and extremely high Mohs hardness (7). This is only exceeded by three natural minerals, each of which has been used for abrasive polishing throughout history:

  • Topaz (8)
  • Corundum (9)
  • Diamond (10)

Corundum has a similarly rich history in abrasive polishing. It is the naturally-occurring form of aluminum oxide (Al2O3), the second hardest naturally occurring substance currently known, and was first implemented as an abrasive at industrial scales as part of the corundum—iron compound emery. Yet there is evidence to suggest that crushed corundum was used as an abrasive in China as early as 5,000 BCE. Sources even argue that engineers in Ancient Egypt were exploiting diamond-based powders in abrasive polishing as early as 3,500 BCE.

Although mankind has been using super-hard minerals for abrasive polishing for millennia, it is only comparatively recently that we have made strides in super-abrasive and freely sintered abrasive materials. Sintered alumina grains currently set the industry benchmark for abrasive polishing, with blasting technologies gradually moving away from cheap quartz-based polishing due to operational and health concerns associated with the mineral.

Engineered Grains: Next Step in Abrasive Polishing

Sintering abrasive grains were a key development in blasting and polishing technologies. It introduced new degrees of quality assurance and control (QA/QC), enabling engineers to maintain tight control of the abrasive grit size and composition. Particles could now be engineered with microscale dimensions to unlock previously impossible levels of precision for surface finishing via blasting techniques.

Being able to sinter alumina grains in workshop conditions with comparable hardness properties to the bulk material meant that a new gold standard was established for blasting media in both industrial and proprietary abrasive polishing sectors. This paved the way for novel engineered grains based on new material compositions.

 

Engineered Grains from Saint-Gobain

Saint-Gobain Abrasive Grains has developed a new engineered grain based on sintered bauxite. Spartan Blasting Media is produced with efficient control of grit shape and size, from 16 – 80 grit, ensuring tailored control of surface finish for a range of downstream materials. Unlike conventional abrasive polishing media, Spartan particles are designed from the ground-up with a focus on improving safety, productivity, and reliability.

If you would like more information on how Spartan products are innovating the abrasive polishing market and moving beyond ancient materials for a safer, more efficient future, read our previous blog post: Spartan Blasting Media from Saint-Gobain. Otherwise, contact a member of the team with any questions.