Fretting Wear Behavior of UHMWPE Under Different Temperature Conditions

ABSTRACT

The fretting wear behavior of ultra-high molecular weight polyethylene (UHMWPE) against a GCr15 steel ball was investigated using an Optimal SRV-IV oscillating reciprocating friction and wear tester (Optimal Corp., Germany). The influence of temperature, stroke size and frequency was studied in detail under a normal load of 10 N. The results showed that the friction coefficients initially decreased and then increased afterward with the increasing of temperature, having the lowest value at 0°C. The wear loss of UHMWPE at a stroke of 100 µm showed a similar tendency as the friction coefficients, but monotonously increased with increasing of temperature for a stroke of 200 µm. According to an analysis of the worn surface, it was concluded that abrasive wear accompanied with local plastic deformation dominated the wear mechanism in the process of the fretting test at −30°C. The plastic deformation was slightly less at 0°C than that at −30°C. With the increasing of temperature, the hardness of UHMWPE decreased significantly, plastic deformation and adhesive wear became more severe. In addition, a lubricating transfer film was formed on the steel ball.

KEYWORDS:

• fretting wear
• friction mechanisms
• hardness
• polymer
• temperature
• transfer film

Funding

This work was financially supported by National Natural Science Foundation of China (Grant No. 51405478) and National Basic Research Program of China (973 Program, Grant No. 2014CB643302).