Sialon Grade meets performance of whisker ceramics.

Press Release Summary:

Kyon 1540 sialon (silicon nitride/aluminum oxide/aluminum nitride) ceramic grade handles roughing through finishing processes on cobalt-, iron-, and nickel-based high-temperature alloys. Formulated from 30% alpha and 70% beta sialon, product is offered in round, square, diamond, and triangle negative insert geometries as well as v-bottom round positive insert geometries. Styles are also available without holes.

Original Press Release:

New Sialon Grade Provides Performance Equal to More Expensive Whisker Ceramics

(Latrobe, PA -- January 17, 2003) Kennametal has introduced a new sialon (silicon nitride/aluminum oxide/aluminum nitride) ceramic grade - Kyon 1540 -- that provides performance equal to much more expensive whisker ceramics in turning high temperature alloys. The new grade will be displayed at Kennametal's exhibit in booth E-2105 at IMTS 2002. The new grade is designed for general purpose machining, from roughing through finishing, of a wide range of cobalt-, iron- and nickel-based high temperature alloys, including Inconels, Hastelloys, and Waspalloys. A new material formulation and improved processing provide higher strength and wear resistance versus other sialon materials. "Kyon 1540 provides improvements in both productivity and tool life compared to competitive sialon grades, and equal performance to whisker ceramics at a substantially lower cost," said Tally Persichetti, Product Manager for Ceramic Materials for Kennametal. "We have also seen a performance improvement in applications where whisker ceramics fail due to depth of cut notching."

Kyon 1540 provides a unique material formulation - 30% alpha and 70% beta sialon. Alpha and beta sialon represent different phases or crystalline structures. Alpha grains are generally equiaxed while beta grains have a whisker structure. The high proportion of alpha sialon in Kyon 1540 increases the wear resistance of the new material. Optimizing the aspect ratio of the beta grains increases the toughness. "In this case, we were able to overcome the traditional tradeoff between toughness and wear resistance," said Russ Yeckley, Manager, Ceramic Technology for Kennametal. He added that the new materials are much less expensive than whisker ceramics because the latter require more expensive hot pressing methods while Kyon 1540 is made with conventional powder metallurgy.

Tests against existing sialon materials used in machining high temperature alloys show dramatic improvements in performance. In machining Inconel 718, at 800 surface feet per minute (sfm), 0.007 inch per revolution (ipr) feed rate, and 0.15 inch depth of cut (DOC), Kyon 1540 provided twice the tool life of a competitive sialon ceramic. The new ceramic material made it possible to increase feed, speed, and depth of cut to 1,000 sfm, 0.120 inch DOC, and 0.010 ipr feed rate in cutting Inconel 706 compared to Kyon 2000, Kennametal's previous general-purpose high temperature alloy turning grade. In two Inconel 718 applications, at 1000 sfm, 0.125 inch DOC, and 0.006 ipr feed rate and at 700 sfm, 0.15 inch DOC, and 0.005 ipr feed rate, Kyon 1540 provided equal performance to a competitive whisker ceramic.

Kyon 1540 is currently offered in round, square, diamond, and triangle negative insert geometries as well as vee-bottom round positive insert geometries. Styles are available without holes for use with Kendex toolholders and with holes for use with Kenloc toolholders. "We will soon offer styles that can be used in our Top Notch Turning system," Persichetti said. "Kyon 1540 will replace our existing Kyon 2000 general-purpose grade and complement Kyon 2100, which is primarily targeted at finishing applications."

For more details on Kyon 1540 inserts and other Kennametal metalcutting products, please call 800-446-7738 or visit


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