Polyimide (Kapton) was implanted with He+ ions at energies of 1MeV

1 5MeV

2MeV

respectively

and its surface hardness and wear resistance were characterized.Results of tests indicated that hardness values of all implanted specimens increased over those of the unirradiated material

particularly for specimens implanted at 2MeV.The hardness improved from 0.55GPa for unimplanted Kapton to 6.7GPa

corresponding to a factor of improvement of about 12.Reciprocating sliding wear tests using a steel ball counterface yielded significant improvements for the 1MeV energy implantation. A similar wear improvement was not obtained for the other two energy implantation.It showed that optimum wear properties did not exist at the highest implantation energy but rather at an intermediate energy.These improvements in properties are apparently related to the effectiveness of cross-linking.The results of X-ray photoemission spectroscopy (XPS) proved that after irradiation

the contents of O

N atoms decreased in the surface and a new three-dimensional covalent bonded structure

mainly constructed by phenyl

was formed.