Biomimetic fabrication, mechanical behavior and interrupted turning performance of the microscopic surface structures of Al2O3/TiC micro-nano-composite ceramic

Abstract

The present work was conducted to study biomimetic fabrication, mechanical behavior and interrupted turning performance of the microscopic surface structures of Al2O3/TiC micro-nano-composite ceramic. A novel nondestructive method for fracture toughness assessment and two novel performance indicators with critical influencing factors integrated were proposed for the biomimetic microscopic structures. Laser surface texturing (LST) was employed to fabricate the biomimetic microscopic structures considering the structures on the cuticle of both catharsius molossus and carassius auratus. The fractal dimensions of the indentation-caused microscopic cracks and the laser-caused microscopic cracks were gained and analyzed. The external load in cutting process, the microscopic structure within the composite ceramic and the resistance to fracture of the composite ceramic were integrated in the proposed performance indicators I1 and I2. The number of scans and the angle of laser beam had substantial influences on the sloping characteristics of microscopic dimple and microscopic groove. The sloping characteristics of the microscopic dimple were more sensitive to the changes of the number of scans and the angle of laser beam. Higher degree of oxidation of the biomimetic microscopic structures corresponded to greater reduction of fracture toughness. The fractal dimensions of the indentation-caused microscopic cracks and the laser-caused microscopic cracks can be used to reflect fracture toughness. The fractal analysis of the laser-caused microscopic cracks can be used as a nondestructive method for the assessment of fracture toughness. The biomimetic microscopic structures on ceramic tool surface were found to be effective in postponing tool failure. The optimum interrupted turning performance of the biomimetic microscopic structures can be acquired when the number of scans was 2 and the angle of laser beam was 50°. Indicator I1 had a higher accuracy in the prediction of performance. Indicator I2 can be utilized to predict the performance of the biomimetic microscopic structures without destruction.