Morphology and microstructure of polyamide 46 wear debris and transfer film: In relation to wear mechanisms

The morphology and microstructure of PA46 wear debris and transfer film were studied by using scanning electron microscopy (SEM), Fourier transform infrared spectrometer (FT-IR) and X-ray diffractometer (XRD) for understanding the physical and chemical changes of PA46 caused by friction. An acid-eroding method was used to peel the transfer film from the mated steel ring surface. It was found that PA46 molecules happened directional arrange along the friction direction both in the transfer film and on the worn surface. PA46 formed two different shapes of wear debris: belt-like and spiral rod-like wear debris, which related to different wear mechanisms of PA46 during sliding process. Compared to the PA46 bulk, the crystal state in the transfer film and wear debris decreased and the amorphous structure increased. The main wear mechanisms of PA46 against steel were suggested to be adhesive wear and melting flow.