Evaluation of cutting tools secondary adhesion wear using 3D optical topography techniques. Application to dry turning of Al-Cu aerospace alloy

摘要

The combination of specific properties, cost, reliability and predictable behavior, guarantee that the aluminium alloys will be kept as one of the materials used in aerospace industry. When aluminium alloys are machined, transfer of cutting material to cutting tool is related with the secondary or indirect adhesion wear mechanism, which can be presented in form of Built-Up Layer (BUL) and Built-Up Edge (BUE), located in two defined zones of the tool, cutting edge and rake face respectively. The material adhered involve tool properties, geometrical and physicochemical alterations which modify the initial cutting conditions, in accordance with currently concept of tool wear. Until now, a generalized lack is observed in methodologies to assessment the secondary adhesion wear in machining of aluminium alloys, mainly due to the difficulty found in characterizing and quantify thereof. In this paper, based in Focus-Variation Microscopy (FVM) techniques, a methodology is proposed through high-resolution optical 3D topography measurements obtained from WC-Co worn tools tested in the dry turning of UNS A92024-T3 alloy, in order to obtained information about effects and intensity of secondary adhesion wear.