Estimation of flank wear growth on coated inserts

Abstract: The present work was conducted in Sandvik Coromant to enhance the knowledge and understanding of general flank wear growth and specifically in this case flank wear growth on the cutting edge of the coated (Ti(C, N)/ Al2O3/ TiN) tool inserts.   Reliable modeling of tool life is always a concern for machining processes. Numbers of wear models studies predicting the tool life length have been created throughout the metal-cutting history to better predict and thereby control the tool life span, which is a major portion of the total cost of machining.   A geometrical contact model defining the geometry of the flank wear growth on the cutting tool inserts was proposed and then compared with four suggested models, which estimates flank wear. The focus of this work is on the initial growth of flank wear process and thereby short cutting-time intervals are measured.   Wear tests on cutting tool inserts were performed after orthogonal turning of Ovako 825 B steel and were analysed by optical instrument, 3D optical imaging in Alicona InfiniteFocus and EDS in SEM. Force measurements for cutting speeds, Vc, 150, 200, and 250 m/min and feed rate, fn, 0.15 mm/rev were recorded as well.   Results show that initial flank wear land, VB, growth is dominated by sliding distance per cutting length for different cutting speeds. A good correlation between the geometrical contact model and estimation models is indentified. The cutting force measurements compared with the flank wear land show proportionality between two parameters. For the machining data in the present study the flank wear rate per sliding distance, dW/dL, is estimated to 2x103 (μ3/m).