The Evolution of Vitrified Grinding Wheels (Part 3)

Vitrified Superabrasive wheels use either diamond or CBN in a glassy or ceramic bond. Conventional grinding wheels use either Aluminum Oxide or Silicon Carbide, as with all grinding wheels, the bond imparts certain characteristics, making it better suited to some applications than others.

ADVANTAGES

  • High strength structures with porosity for clearing chips and bringing coolant to grinding zone allow for reduced grinding cycle times.

  • Porosity for coolant and chip removal efficiently remove heat and reduce work piece thermal damage and stresses.

  • Efficient chip removal reduces wheel dressing frequency thus prolonging wheel life thus lowering machine down time for wheel changes and lowering waste removal costs.

  • High wheel stiffness, long wheel life, and minimal heat generation allow for excellent finish and dimensional tolerancing.

  • Wheel specifications can be optimized for each specific application (machine, coolant, work piece, stock removal, dressing, etc…)

  • High product uniformity and performance allows for continuous unmanned grinding operations.

  • Automated dressing and wheel conditioning.

LIMITATIONS

  • Wheel manufacturing process controls need to be tight to ensure repeatability and product consistency (most sensitive of bond systems to process variations).

  • Wheel designs need to be matched to the application (i.e. solid Vitrified wheels are limited to 80m/s operation, Vit wheels with steel cores can be rated for use up to 170m/s operation).

  • Wheel prices may seem high when compared with conventional or other Superabrasive grinding wheel prices (need to look at all costs, not just wheel price).

  • Significant capital investment in terms of equipment to maximize cost benefits of higher concentration CBN and Diamond Vit wheels for high volume applications.

  • Generally requires knowledge of complete grinding process to maximize grinding performance. Grinding application support is necessary in many applications

  • Difficult to cross reference competing manufacturers wheel specifications

APPROPRIATE APPLICATIONS

Vitrified CBN grinding wheels are ideal for high volume applications where productivity is paramount such as Automotive applications like Cam & Crank shaft grinding, and Aerospace engine component grinding. Recent advances in bonds and wheel specifications has led to the development of wheel structures for use on older less suitable grinding equipment and applications like surface and cylindrical grinding in mold and die shops.

Vitrified diamond grinding wheels are most suited for grinding of very hard Ceramic and Carbide materials. Applications include grinding of PCD and PCBN cutting toolings, structural ceramic components, and Carbides.

CURRENT RESEARCH

  • Improved bond and wheel strength through continuing work with “Ceramic” bonds.

  • Abrasive grit customization for better chemical and mechanical bonding in existing and new “Ceramic” bonds.

  • Improved understanding and modeling of the grinding process.

STILL EVOLVING

Vitrified Diamond and CBN wheels compositions continue to evolve through the use of new chemistries and processing variables to enhance grinding wheel structures and performance. When it comes to grinding hard to grind materials, there are no better abrasives than Superabrasives; Diamond and CBN. Vitrified structures combined with Superabrasives often times allows for the best compromise between wheel life and grinding performance, thus giving the lowest overall costs in grinding.

ProductsStacy ViggianoVitrified Grinding Tools