Tungaloy AH905, PVD-coated inserts – Innovative solution for turning high-temperature alloys

Market trends have shown an increasing popularity of high-temperature alloys in many industries, particularly aerospace, power generation, oil and gas, and even automotive sectors. When machining high-temperature alloys, cutting tools tend to break down quickly, shortening tool life. Customers in these industries demand high productivity and reliable tool life for these “difficult-to-cut” materials.


Responding to these market demands, Tungaloy has introduced the grade AH905, PVD-coated inserts, in combination with the HMM chipbreaker, which are both specially designed for turning of high-temperature alloys.

PVD coated grade “AH905”
AH905, designed specifically for turning high-temperature alloys with its exclusive cemented carbide substrate, delivers well-balanced hardness and toughness. This substrate has strong resistance to high temperature, thus demonstrates exceptional chipping resistance in super-alloy turning. The coating layer offers high adhesion strength and smoothness which allows better oxidation resistance than the conventional coatings. This PVD coating also provides excellent wear resistance. The ideal combination of substrate and coating offers stable and long tool life when machining high-temperature alloys.

“HMM” type chipbreaker
The unique HMM chipbreaker is designed exclusively for turning high-temperature alloys. The HMM chipbreaker has a large rake angle and distinctive protrusions to reduce the cutting force and contact area between rake face and chips. These features inhibit heat penetrating the insert by directing it into the chips. The HMM chipbreaker prevents the adhesion of chips on the cutting edge, thereby reducing damage, such as notch wear or sudden fractures.

Positive inserts extended in Tungaloy’s “AH905” grade for superalloy turning
A line of positive inserts have been incorporated into Tungaloy’s AH905 grade for turning super alloys and other difficult-to-machine materials in the aerospace and power-generation industries. Featuring PremiumTec surface technology, the inserts improve productivity by preventing chip adhesion and improving chip flow. AlTiN PVD coating improves wear resistance for consistent performance and increased tool life. The inserts are available with six types of chipbreakers for medium to finish-cutting applications. These chipbreakers include PSF, PSS, PS, RS, 61 and all-round chipbreaker types.


The PSF is designed for machining with low cutting forces and is well-suited for finish-turning operations, the company says. It can turn at low depths of cut to decrease the potential for chip-control issues.

The PSS chipbreaker is well-suited for light machining and internal turning operations, the company says. The PS geometry is an “M” class insert developed for highly productive boring operations.

To accommodate light to medium cutting of super alloys, the RS and 61 chipbreakers have been applied in round inserts. The RS adopts a large rake angle to optimise chip control, while the 61 offers high-feed turning at small depths of cut. The company’s all-round chipbreaker is suited for a range of continuous and interrupted machining processes, generating low cutting forces with improved chipping resistance.

For further details contact Star Tooling on TEL: 011 818 2250 or visit www.startooling.co.za or www.tungaloy.com