Comparative Studies on Friction and Wear Performance between Glass-fiber Reinforced Polyamide 66 Composite and Ductile Irons on Ceramic Al_2O_3 Counterface in Sucker Rod Centralizer Application

摘要

The tribological behaviors of three materials for sucker rod centralizer application including glass-fiber reinforced polyamide 66 composite, ductile iron and quenched ductile iron were investigated on the pin-on-disc type wear testing machine against ceramic Al_2O_3 under both dry sliding and oil field water lubricated conditions. Laser optical microscopy, scanning electron microscopy, Fourier transform infrared spectrometer, digital temperature measurement system and X-ray photoelectron spectroscope were used to investigate the microstructure, wear mechanism and chemical nature change of the studied materials. The results revealed that the coefficients of friction under oil field water lubricated condition were slightly lower than those under dry sliding condition for the studied materials, in which glass-fiber reinforced polyamide 66 composite exhibited the lowest coefficient of friction. The quenched ductile iron showed the lowest wear volume among the studied materials under both dry and lubricating sliding conditions. The wear loss of glass-fiber/polyamide 66 composite was much higher under lubricating condition than that under dry sliding condition, and much higher than those of as-cast and quenched ductile iron, which was attributed to the combination of thermal deformation, degradation and micro-ploughing.