Process-secure machining of super alloys

WNT has developed HCN5110 and HCN5115 problem solver grades with new indexable inserts specifically for turning titanium and super alloys. The hard substrate, the new PVD coating based on TiAlN and a specific chip breaker make economic and reliable machining possible on these difficult materials. Typical problems such as cold working and extraordinary wear of tools belong in the past. The WNT Mastertool Dragonskin product range offers for the first time particularly high heat and wear resistant indexable inserts for the treatment of titanium and super alloys. The HCN5110 grade has a very hard, abrasion resistant substrate and high wear resistant coating for the machining of titanium and titanium alloys, while HCN5115 is ideally suited to super alloys as it has an extremely edge-stable substrate and friction-minimizing coating. Materials with a complex alloy composition (iron, nickel, platinum, chrome or cobalt based with additives of other elements), which are temperature resistant are for example Tribaloy, Hastelloy, Incoloy, Inconel and Nimonic.

Both new grades offer the chip breaker designed for super alloys - M34. With this geometry special emphasis was put on minimizing possible heat development. Extremely sharp edges provide for optimum cutting and therefore a reduction of the forces. The cutting depth, depending upon insert geometry can be up to 4.5 mm. The cutting speed lies within the range of 30 m/min to 90 m/min.

Super alloys are used particularly for high-quality parts, which are exposed to high temperatures. In particular engine components for aviation, but in addition, valves and pumps for the chemical industry as well as temperature-burdening parts for power stations, catalysts and kitchen utilities.
The alloys for such applications, which are based on cobalt, nickel or heat resistant steel, cause problems with machining. For example the small heat conductivity of the alloys means that when cutting, heat is hardly exhausted, so very high temperature stability of the tool is required. This heat development leads to a structure change with further hardening of the material (cold working).

This requires even higher robustness of the tool than the high hardness the super alloy already requires to machine it. The high hardness leads to increased crater wear, which is caused by the flow of chips over the indexable insert. The two WNT indexable insert grades HCN5110 and HCN5115 are appropriate for these high requirements and enable machining of these super alloys reliably and productively.
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