Wear mechanisms of polyetheretherketone composites filled with various kinds of SiC

Abstract

Nanometer SiC, micron SiC, and whisker SiC were used as fillers in polyetheretherketone (PEEK) and the influence of these fillers on the friction and wear of the PEEK composites was studied. The composite specimens with various kinds of SiC were prepared by compression moulding. Their friction and wear properties were investigated under ambient conditions in a block-on-ring machine by running a plain carbon steel (AISI 1045 steel) ring against the PEEK composite block. The morphologies of the wear traces and wear debris were observed by scanning electron microscopy (SEM). Experimental results showed that all these fillers reduced the friction of PEEK and that 10.0 wt.% nanometer SiC as filler was very effective in reducing the wear of PEEK. The wear rate of PEEK filled with 10.0 wt.% whisker SiC was almost unaffected. SEM analyses indicated that severe abrasive wear occurred on the worn surfaces of PEEK composites filled with micron sized SiC and whisker SiC. In the case of the carbon steel ring/nanometer SiC filled composite block, a thin, uniform, and tenacious transfer film was formed on the surface of the steel ring surface. The wear mechanisms of PEEK composites filled with nanometer SiC, micron SiC, and whisker SiC were different.