Posted November 7, 2023

New steel turning grade for high-feed roughing

In addition to the new GC4405, Sandvik Coromant recently introduced the GC4425 and GC4415 steel turning grades. These next-generation grades have been fully refined, delivering an average 25 percent increase in tool life compared to the previous grades.

Coromont GC4415 steel turning grades“With the introduction of GC4405, we are complementing the steel turning grade chain within the high-feed roughing area,” says Torbjörn Ågren, product application specialist at Sandvik Coromant. “We strive to make it as easy as possible to choose and apply the correct grade to match the specific application.”

Grade GC4425 delivers wear resistance, heat resistance and toughness in a wide application range, while grade GC4415 complements GC4425 with enhanced performance when more heat resistance is needed. Grade GC4405 should be applied as a high-feed productivity optimizer with high metal removal rates in stable conditions with demanding plastic deformation properties.

Among the features offered by the GC4405 is a new carbide substrate with optimized microstructure, which reduces plastic deformation in high-feed applications. The substantial increase in plastic deformation resistance has enabled a drastic expansion in the application range toward harder steels and higher productivity compared to the existing grade GC4305.

The new grade GC4405 features the second-generation Inveio® technology coating, which is designed specifically to combat crater wear common to P05 applications. What makes second-generation Inveio different from the earlier generation is the alumina coating, where the crystals are aligned even more vertically toward the top surface to improve wear resistance, offering more consistent quality and performance.

The GC4405 offers a considerable increase in productivity and tool life, particularly when machining steels above 300 HB. The new grade is also suitable for machining softer steels without the need for coolant, offering substantial opportunities for more sustainable machining.

Comprehensive tests conducted between the existing GC4305 and the next-generation GC4405 steel turning grade indicate an increase in tool life ranging from 30 percent up to 130 percent, which is primarily thanks to significant improvements in the plastic deformation and crater wear resistance.

Grade GC4405 is recommended for continuous roughing to semi-finishing in stable conditions and long time in cut. It is suitable for high-feed machining with medium, roughing or wiper geometries in harder steels above 300 HB, or for high-feed and/or high-speed machining in softer steels below 300 HB.

The grade should be applied in ISO application area P05 (P01–P10). It is optimized for P2.5 low-alloy hardened steel but also recommended for high-productivity applications in low-alloy P2.1 and unalloyed P1.2 steel.