Effect of solution-blown polyamide-6 nanofiber interlayer on drilling performance of carbon fiber reinforced composites

Abstract

This study examines the effect of solution-blown polyamide-6 (PA6) nanofiber interlayers on the drilling performance of carbon fiber reinforced polymer (CFRP) composites. Results demonstrate that PA6 nanofiber interlayers significantly reduce drilling thrust force and improve surface quality. Specifically, at a spindle speed of 1000 r/min and a feed rate of 1500 mm/min, the maximum thrust force was reduced by 17%, from 683.33 N in neat composites to 583.13 N in nanofiber-reinforced composites. At a higher spindle speed of 8000 r/min and a feed rate of 500 mm/min, thrust force decreased by 18%, from 80.22 N to 65.46 N. Surface roughness analysis revealed that nanofiber interlayers reduced Ra values by up to 44%, with a minimum roughness of 0.529 µm compared to 1.196 µm in neat composites. Optical and SEM analyses confirmed fewer plucking zones, reduced fiber pull-out, and improved fiber-matrix bonding in nanofiber-reinforced samples, particularly at higher spindle speeds. These findings indicate that PA6 nanofiber interlayers enhance drilling performance, offering reduced machining forces and superior hole quality for precision applications in the aerospace and automotive industries.