Effect of Electron Radiation on the Tribological Properties of Polyimide

The blocks of polyimide (PI) were irradiated with 1.7 MeV electrons in four doses of 1 × 10 5 , 5 × 10 5 , 2.5 × 10 6 , and 5 × 10 6 Gy under N 2 atmosphere. The changes of the polyimide surface after radiation were characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS), whereas the friction and wear behavior of both the pristine and irradiated samples were investigated with an M-2000 friction and wear tester at room temperature under ambient atmosphere. The results revealed that electron radiation did not exert much influence on the friction coefficient of PI under the experimental conditions. In contrast to the friction coefficient, the wear rate decreased with an increasing radiation dose. The reason for the changed tribological properties of the polyimide was mainly due to the structural and the compositional changes in the surface induced by radiation.