Research on the Tribological Behavior of Copper-Graphite Self-Lubricating Material Paired with the Counterparts with Different Surface Treatments

Abstract

Reasonable matching can improve the service life of the friction pair of tire active molds， but there is a lack of research on the matching of tire active molds under actual friction conditions.In view of this situation，a study was conducted to provide guidance for the rational selection of friction pairs for tire active molds.To simulate the actual friction conditions of tire active molds，test equipment was independently developed.Laser quenching test blocks， Ni-P alloy test blocks and QPQ (nitrogen-carbon-oxygen composite treatment technology) test blocks were respectively employed to be paired with the copper-graphite self-lubricating material.Additionally， the friction coefficient， wear loss，morphology and composition of the worn surface and debris of the three groups of friction pairs were compared， and the mechanism of friction and wear was explained.Results showed that when paired with copper-graphite self-lubricating material， the friction coefficient curves of laser quenching test block and QPQ test block were gentle and stable，while the friction coefficient curve of Ni-P alloy test block had a large fluctuation range.Moreover， the order of the average friction coefficient from small to large was laser quenching test block < Ni-P alloy test block <QPQ test block.During the friction process，the laser quenching test blocks were constantly worn out in the form of abrasive wear，the QPQ test blocks were basically not worn out，and the surface was only slightly worn out by abrasive wear，while the Ni-P alloy test blocks had no surface damage.When paired with laser quenching test blocks，the copper-graphite self-lubricating material was damaged in the form of abrasive wear，adhesive wear and fatigue wear.In the Ni-P alloy/copper-graphite friction pair， the copper-graphite self-lubricating material was mainly damaged in the form of adhesive wear.In contrast， the copper-graphite self-lubricating material was continuously worn in the form of abrasive wear when paired with QPQ test blocks.The order of the wear amount from small to large was QPQ test block < laser quenching test block < Ni-P alloy test block.Considering the wear of the friction pair， the QPQ test block was the most suitable for pairing with copper-graphite self-lubricating material and had the longest service life.

Keywords

• laser quenching； ni-p alloy； qpq(nitrogen-carbon-oxygen composite treatment technology)； copper-graphite self-lubricating material； friction and wear