Effects of dual biomimetic tool surface microstructure on specific cutting energy in green turning

The energy consumption in the tool-workpiece system is dominated by specific cutting energy (SCE). Reducing SCE is critical for energy conservation in continuous dry turning which is a typical green turning process. The application of biomimetics shows great promise for reducing SCE. This study investigated effects of dual biomimetic tool surface microstructure on SCE in green turning. The dual biomimetic microstructure was established considering the rheological feature of the flow zone, the fierce cutting load and two kinds of biological structure. A theoretical rheological indicator was proposed for the flow zone in the secondary deformation zone. Furthermore, theoretical model was derived for SCE on the basis of the rheological indicator. It was found that the fabricated dual biomimetic microstructure reproduced the designed geometry characteristics. The SCE in green turning was reduced due to the existence of the dual biomimetic microstructure. A suitable area density Ad (27.66 %) of the microstructure should be adopted for efficiently reducing SCE. The variation of SCE was sensitive to the change of the rheological indicator. Larger parameter Pbm, the ratio of laser angle to microstructure element area, should be utilized for the microstructure element to acquire even lower rheological indicator and thereby obtain even greater reduction of SCE. Moreover, growth of the reduction rate was obvious only when Pbm was lower than 1.2 * 109 degrees /m2. The combination of Ad with a value of 27.66 % and Pbm with a value of 1.2 * 109 degrees/ m2 can result in 34.72 % reduction of the total SCE compared to conventional tool.