Milling Cutters for Ceramic Inserts Offer Extreme Toughness

Walter USA’s M2472 and M2473 milling cutters with ceramic button indexable inserts provide optimal reliability and toughness for increased productivity, the company reports. The M2472 cutter body accepts positive ceramic inserts, and the M2473 cutter body accepts double-sided ceramic inserts with eight or more cutting edges per indexable insert. The cutting diameters (Dc) range from 32-63 mm.

The ceramic insert grades are based on silicon, aluminum, oxygen and nitrogen (SiAlON). The WIS10 SiAlON grade is designed for stable conditions and offers high wear resistance. The WIS30 SiAlON grade is targeted for universal applications due to its extreme toughness.

Both grades are said to be the top choice for milling applications because of their high resistance to thermal shocks as the cutting edge enters and exits the workpiece material. In addition, the inserts can be used without cooling lubricant, where compressed air or minimum quantity lubrication is applied.

The M2472 and M2473 milling cutters bodies are ideal for roughing heat-resistant superalloys (ISO S workpiece group), such as Inconel, Incoloy, Monel, Nimonic, Haynes, Stellite, Udimet, Wapaloy and Hastelloy alloys.

To protect the cutting edge when the tool enters the cut, Walter recommends using the “roll-in” strategy in which the width of cut is gradually increased after the insert initially engages the workpiece to reduce shock and vibration. This strategy imparts finer surface finishes and increased tool life.

New and innovative clamping wedges for securing the inserts feature internal cooling grooves and a TiN coated surface. Potential benefits of these clamping wedges include protection against material weld formations due to the coating on the clamping wedges, and protection against excessive heat produced when milling because of a targeted compressed air supply using these wedge-type clamps.