CBN grinding gets major lift from advanced glass bonding technology: wheel life soars by 50% to 200%.

What happens when a manufacturer of grinding wheels (Universal Superabrasives) takes the most advanced glass bonding technology of its parent company (Saint-Gobain Abrasives) and applies it to the most advanced cubic boron nitride (CBN) grains commercially available?

The answer for grinding wheel manufacturer Universal Superabrasives is its new T2 technology platform, which allows CBN wheels to be customized to meet user requirements by specific application and material type. The result: dramatic improvement in cycle time and wheel life.

The T2 bonding technology incorporates either high-strength glasses or glass-ceramic bond systems custom designed to maximize strength, stiffness, and wear resistance. Wheels using this technology are designed for high-volume, ultra-precision ID and OD grinding of a range of parts manufactured from a variety of ferrous materials, including cast iron, steel, and high-nickel alloys.

Productivity gains of from 50 to 200 percent in wheel life compared with wheels using standard bond systems--as measured by total parts ground per wheel--have been demonstrated for manufacturers of automotive parts (cam- and crankshafts, bearings, and fuel injectors) as well as for aerospace manufacturers of jet engine blades, among other parts.

Saint-Gobain Abrasives expects this niche precision grinding market to grow 10 percent a year over the next 20 years reaching more than $160 million in 2023, compared with $32 million in 2003, according to Dr. Mike Hitchiner, PhD, vitrified CBN product manager-precision superabrasives.

The tougher CBN abrasive grains for precision grinding that have become available on the commercial market over the last few years have needed a new bonding technology.

Saint-Gobain Abrasives through its international R&D efforts and collaborative research efforts at the Oak Ridge National Laboratories, under a U.S. Department of Energy contract, investigated the effect of grit size distribution and toughness in standard wheels and the newly-developed bond systems. They compared the performance of traditional CBN grades in standard vitrified bond wheels with the new higher strength bonds developed by Saint-Gobain Abrasives R&D and determined that tougher grits required these stronger, more resilient bonds to provide economic benefit.

Later in the 15-month development cycle, Universal Superabrasives tested and verified formulations of the new CBN grains in its new vitrified bond platform at Oak Ridge and in applications at automotive and aerospace companies working with their machine tool builders, including such companies as Campbell, Guistina, Landis, and United Grinding Technologies.

The new vitrified bond CBN wheels had important processing implications, enabling manufacturers to lower costs and increase productivity by replacing machining and hard turning. And they are said to be ideally-suited to peel grinding where high wheel speeds and high work speeds can achieve very high stock removal rates with low grinding forces for a given spindle horsepower.

Typically, users can grind up to three times the stock with half the force, compared with conventional grinding processes, says Dr. Hitchiner. To maximize grinding efficiency, metal removal is conducted in a very small width, turning the wheel into the equivalent of a single-point cutting tool. Users contour-grind time part as if the wheel were being used in machining. Saint-Gobain Abrasives, www.rsleads.com/4061p-161