Cutting performance and wear of ZTA-TiO2-Cr03 mixed ceramic cutting tools when turning stainless steel 316L

Abstract

The ZTA-TiO2-Cr2O3 ceramic cutting tool is a new cutting tool that possesses good hardness and fracture toughness. However, the performance of the ZTA-TiO2-Cr2O3 cutting tool is still unknown and needs further study. In this research, the cutting performance and wear of the ZTA-TiO2-Cr2O3 mixed ceramic cutting tools in turning stainless steel 316L are investigated. The tool wears of the ZTA-TiO2-Cr2O3 cutting tool and the surface roughness of the machined surface of stainless steel 316L are investigated, and the empirical model for predicting the tool wear was generated. Finally, the comparison of the ZTA-TiO2-Cr2O3 and Sandvik ceramic cutting tool is investigated. Preliminary experiments are conducted to set the range of machining where the spindle speeds are in the range of 1000 to 1450 rpm, feed rate from 0.1 to 0.15 mm/rev, and depth of cut of 0.2 mm. Measurements of wear were considered in the analysis before the final parameters were designed for machining. In the design of the experiment, the parameters used for the spindle speed are in the range of 907 to 1543 rpm, feed rate from 0.08 to 0.22 mm/rev, and depth of cut of 0.2 mm. Bridgeport ROMI PowerPath CNC lathe machine is utilized to conduct the turning operation for the experiment. Analysis of the flank wear and crater wear were performed by using an optical microscope (NIKON MM-4001L), while the chipping area was observed by scanning electron microscopy, SEM (JEOL JSM-IT100). The surface roughness of the machined surface is measured via portable surface roughness (Mahr MarSurf M3000C). In the preliminary experiment, the flank wear, crater wear, and surface roughness are decreasing when the spindle speed increased from 1000 to 1450 rpm and the feed rate increased from 0.10 to 0.15 mm/rev. The results obtained from the actual experiment are analyzed by using Design Expert 11 software. It is found that the spindle speed is a significant factor that affects the flank wear and the surface roughness of the machined surface, while the crater wear is more affected by the feed rate of the machining parameters. The optimum cutting parameters are when the spindle speed of 1421.38 rpm, and the feed rate of 0.10 mm/rev. It shows that the cutting tool has good potential in high-speed machining. The comparison between the cutting tool produced in this research and the commercial cutting tool shows that the wear performance of the ZTA-TiO2-Cr2O3 ceramic cutting tool is lower than the Sandvik commercial ceramic cutting tool. Even though the commercial cutting tool has superior properties, the fabricated ceramic cutting tool shows some promising aspects such as cutting at a higher speed.