This part of ISO 8688 specifies recommended procedures for tool-life testing with cemented carbide tools used for face milling of steel and cast iron workpieces. It can be applied to laboratory as well as to production practice. The cutting conditions in face milling may be considered under two categories as follows : a) conditions as a result of which tool deterioration is due predominantly to wear; b) conditions under which tool deterioration is due mainly to other phenomena such as edge fracture or plastic deformation. This part of ISO 8688 considers only those recommendations concerned with testing which results predominantly in tool wear. Testing for the second group of conditions given above is currently under study. This part of ISO 8688 establishes specifications for the following factors of tool-life testing with face milling tools in accordance with figure 1 : workpiece, tool, cutting fluid, cutting conditions, equipment, assessment of tool deterioration and tool life, test procedures, recording, evaluation and presentation of results. Figure 1 — Face milling - Milling operation