Machining of VP20ISOF Steel With Resharpened Carbide Tools in End Milling

The main objective of the present work is to determine the performance of resharpened integral coated cemented carbide end milling tools. Tools as new and after they have been resharpened were tested, during machining of hard steel used in the mold and die industry. The coatings used were TiAlN and AlCrN. The cutting speed was varied, keeping the depth of cut, the cutting width and the feed per tooth constants. Tests were carried out dry. A 2³ factorial design was used, considering the following factors (and levels): cutting speed (80 and 100 m / min), tool coating (TiAlN and AlCrN) and the tool condition (new and reground). The output parameter considered is the tool life (wear rate). At the end of the tool life the wear mechanisms were analyzed within a Scanning Electron Microscopy - SEM. The results showed that in general the AlCrN coated tools outperformed the TiAlN. The performance of resharpened tools was very similar to the new tools, and statistically there is no significant difference between their tool lives.