Machining damage and surface integrity evaluation during milling of UD-CFRP laminates: Dry vs. cryogenic

Abstract

This work demonstrates the sustainable machining of unidirectional carbon fiber reinforced plastics (UD-CFRP) laminates. Surface integrity, machining induced damages, cutting temperature and forces were considered as main output responses to analyze the machining quality at various machining parameters under dry and cryogenic conditions. UD-CFRP laminates with fiber orientations 0°, 45°, 90°, and 135° were chosen as workpiece material. Infrared thermography (IRT) technique was adopted to capture the in-situ cutting temperature for both dry and cryogenic conditions. Results indicate a significant decrease in damage factor, surface roughness and cutting temperature when milling was conducted under cryogenic conditions despite an increase in resultant forces for all fiber orientations. Scanning electron microscopy (SEM) was carried out to capture the micrograph of machined surface, which signifies the change in fiber fracture mode when machining was done under cryogenic conditions. 3D-topography were also performed to assess the surface integrity of machined surface showing improvement in the machined surface quality under cryogenic condition.