Halesowen-based Sandvik Coromant, a cutting-tool and tooling-system specialist, has introduced two new ceramic insert grades for high-speed high-security turning operations on components made from heat-resistant super-alloys (HRSAs) (www.sandvik.coromant.com).

The CC6220 and CC6230 ceramic grades have been developed for applications where whisker ceramics and SiAlON materials “fall short”.

The ability of these new Sandvik grades to accommodate higher cutting speeds contributes to reduced cost per component, while their inherent machining security ensures that quality is not compromised, thereby allowing manufacturers to produce high-quality parts on a repeatable basis.

There is growing demand for aerospace engine parts that can withstand extreme temperatures (beyond the capability of those made from Inconel and other high-performance super-alloys); and while these latest powder-metallurgy materials can be tailored to handle substantially higher temperatures, they are more difficult to machine than common HRSAs.

Along with productivity improvements of more than 50% over whisker ceramics and SiAlONs, CC6220 and CC6230 offer better tool life in challenging HRSAs.

One of the most common applications to benefit from these new ceramic grades will be the machining of turbine discs.

In a customer example, machining a low-pressure turbine disc made from Rene material (42-45HRC) as part of the intermediate-stage machining process, CC6220 RPGX inserts were used to undertake pocketing, while CC6230 RPGX inserts were used for rough-turning operations at cutting speeds up to 400m/min and a metal removal rate up to 80cm3/min.