Kennametal Introduces New SPF Drill for Aerospace CFRP-Cutting Applications

Advanced, lightweight, highperformance, carbon-fiber-reinforced polymer (CFRP) materials are becoming more prevalent in the aerospace industry. The problem is that this material tends to delaminate when being processed, particularly when drilling holes. Kennametal Inc. is answering the call with its new Split-Point Fiber (SPF) Drill. By offering improved hole quality over the entire length of the tool's life, the SPF Drill often can help reduce the cost-perhole by at least 50%.

CFRP composites, now comprising 6% - 7% of current aircraft by weight, are slated to be 40% to 50% of future-generation planes, on average.

The high cutting forces required to machine layer carbon fiber with expensive polycrystalline diamond (PCD) drills cause the material to delaminate, shortens tool life, and contributes to lower productivity.

Kennametal's SPF Drill – with its carbide substrate, positive geometry, and coating – provides longer tool life and requires substantially less cutting force, resulting in the reduction, if not the elimination of delamination.

The drill's smooth CVD multi-layer diamond coating provides more wear resistance and reduced friction, which increases tool life and improves chip flow. Special point thinning increases centering capability and allows reduced thrust, which improves hole quality.

"In field tests, the Kennametal SPF Drill has drilled as many as 300 holes in the most difficultto- machine CFRP-grades without delamination and as many as 1,000 holes without delamination in other grades," says Marcelo Campos, Kennametal's Product Manager for Holemaking.

The new SPF Drill is available in 24 standard diameters, from 0.1719 in. to 0.5010 in., with standard lengths equal to 3x and 5x diameter.

"We also have the ability to produce custom solutions, and can produce drills as long as 7x diameter as a custom solution," says Campos.

KENNAMETAL INC.
LATROBE, PA
KENNAMETAL.COM