Horn Turning Grade Performs in Applications With Variable Hardness

The new SG66 carbide grade is suitable for reliably processing highly temperature-resistant and other difficult-to-machine steel alloys.

Edited by Chris Pasion

Managing Editor, Modern Machine Shop | Production Machining

Horn has developed the new SG66 grade for turning workpieces with varying hardness zones. Featuring a fine-grain carbide, the aluminium-titanium-silicon-chromium-nitride layer delivers high performance when machining hardened steels up to 58 HRC. The maximum allowable temperature is 1,200 °C (2,192 °F). Due to the high flexural strength of the carbide substrate, interrupted cutting is also possible in hardened materials. In addition to hard machining, the carbide grade is also suitable for reliably processing highly temperature-resistant and other difficult-to-machine steel alloys.

The carbide grade SG66 is available for all common Horn insert systems. The in-house coating also enables a short delivery time for special tools. SG66 cannot replace cubic boron nitride (CBN) grades; however, Horn says the grade fills the gap for difficult grooving applications. In comparison, the CBN grade achieves twice the cutting speed and more when machining through-hardened materials.