Sumitomo Electric Hardmetal offers inserts to meet nodular cast iron turning challenge

Sumitomo ACE Coat AC405K has been developed for high speed applications at up to 570 m/min when continuously turning nodular cast iron, and ACE Coat AC415K for general turning, at up to 400 m/min, which can also include continuous and interrupted cuts. In recent years highly ductile nodular cast iron has been chosen in preference to grey cast iron especially in the automotive sector to enable thinner, lighter castings to be used and so contribute to fuel efficiency. However, for machinists the nodular material is more arduous to cut and when cost-per-part is an important consideration, higher spindle utilisation and consistent and predictable performance from cutting tools are priorities. Both AC insert grades are coated with Sumitomo's ultra-hard, multi-layer chemical vapour deposition (CVD) Super FF coating. This recently developed coating incorporates a homogenous structure of ultra-fine ceramic particles that have extreme levels of density with the thin film of titanium carbonitride (TiCN) and a thickened and toughened aluminia film for increased hardness. As a result, says Sumitomo Hard Metal, inserts resist wear and any tendency of the film coating to peel back. In addition Super FF coated inserts resist edge damage and chipping with low levels of chip adhesion (built-up edge).