Influence of Surface Modification on the Cutting Performance of Reaction‐Sintered Al₂O₃–TiOC Ceramics

Abstract

Al2O3–TiC mixed ceramics are popular for dry cutting of hardened steel. In this work, the cutting performance of surface‐modified mixed ceramic cutting tools has been studied. A 1‐μm‐thick modified surface has been obtained by CO2 posttreatment of the Al2O3–TiOC mixed ceramics. The cutting performance of the modified tools has been found to be much better than the precursor‐mixed ceramics. The density of the modified layer also has an influence on the cutting performance. Modified ceramics with a dense surface layer show considerably improved wear resistance compared with that of ceramics with a porous layer. While plastic deformation of the TiC layer in the flank surface, followed by abrasive wear of the exposed substrate is responsible for flank wear, crater wear is caused mainly by diffusion reaction as well as by abrasion. In our system, it is mainly the flank wear that controls the cutting performance of the inserts.

In situ measurement of lattice strains in mixed ceramic cutting tools under thermal and mechanical loads using synchrotron radiation

“…Bending bars of mixed ceramic material with a composition of approximately 65 wt% Al 2 O 3 , 30 wt% Ti(C,O), and 5 wt% ZrO 2 were fabricated according to standard procedure at the Hamburg University of Technology as described in previous works [19,4].…”

“…For example, wear is recorded as a function of time at different parameters such as feed or cutting velocity [3][4][5][6]. From this data, models were developed to predict wear on the tool flank [7].…”

Finite Element Modeling of Tool Stresses on Ceramic Tools in Hard Turning

“…The smallest flank wear was obtained with insert of two layers coating, however the best surface quality was created with multilayer coating. Bhattacharya et al [10] studied on cutting performance of surface modified Al2O3/TiOC mixed ceramic cutting tools. The authors has modified the inserts by posttreatment under argon/CO2 atmosphere to form a TiN layer with a thickness of 1-1.5 µm.…”