Carmex HBA Grade: A New Standard for Threading in Hardened Steel and Super Alloys

by Bernard Martin

As new materials and technology push the limits of metalcutting performance, threadmaking faces new challenges. From hardened tool steels to exotic super alloys, the demand for tooling capable of threading these materials with precision, speed, and longevity has never been higher. Enter Carmex HBA — a carbide threading grade purpose-built to meet the demands of tomorrow’s toughest materials, available today.

Engineered for the Extreme
Carmex Precision Tools Ltd. developed the HBA carbide grade specifically for hard-to-machine materials like hardened steel up to 62 HRc, cast iron, Titanium, and high-temperature super alloys such as Hastelloy, Inconel, and Nickel-based alloys. At the core of HBA’s performance is its extra-fine submicron carbide substrate, offering high toughness and fracture resistance — crucial properties when threading brittle or abrasive materials.

What sets HBA apart is its optimized combination of substrate, coating, and edge geometry. This triad ensures excellent wear resistance, edge stability, and heat resistance — even under aggressive machining parameters.

Versatility Without Compromise
The HBA grade is available for both internal and external threading, supporting 60° and 55° partial profiles, as well as ISO metric and UN thread standards. This broad compatibility makes it a go-to solution for a range of demanding industries, from aerospace to die and mold, where workpieces often feature heat-treated surfaces or hard coatings.

Proven Performance in Hardened Steel
A recent real-world test highlights the capabilities of the HBA grade. In a threading application on D2 tool steel hardened to 53–56 HRc, a 16 ER 1.5 ISO insert was tasked with cutting an external right-hand thread, M32x1.5, over a length of 65 mm.

Running at a cutting speed of 147.6 SFM (45 m/min) — right in the middle of the recommended 100 to 195 SFM range for hardened materials with the HBA grade — the insert completed the thread profile in just 28 passes. It produced 36 threads per edge, showing not only solid productivity but also the kind of consistency and tool life manufacturers expect when working with high-value, hardened components.

A Solution for Hard Machining
As manufacturers continue to push into hard machining to reduce secondary operations and minimize setup time, the need for robust threading solutions grows. Carmex HBA allows users the ability to hold tight tolerances and maintain good surface finishes even in materials that traditionally pose significant challenges to tool life and performance.

Whether you're threading hardened tool steels in automotive applications or cutting threads in heat-resistant alloys for aerospace components, Carmex HBA offers a solution that blends strength, precision, and reliability.

Challenge Accepted
Carmex invites manufacturers, job shops, and engineers to bring their most difficult threading applications forward. With HBA, complex threading in hard and heat-resistant materials doesn’t have to mean sacrificing speed or tool life. Instead, it’s an opportunity to embrace the next generation of carbide performance — tough, precise, and fast. 

Get in touch with Factory Tooling Solutions and one of our team members will answer your questions and run some inserts if we think was can improve performance!