Effect of Blowing Air and Floating Sand-dust Particles on the Friction and Wear Behavior of PTFE, UHMWPE and PI

Abstract

The friction and wear behaviors of polytetrafluoroethylene (PTFE), ultra-high molecular weight polyethylene (UHMWPE), and polyimide (PI) have been comparatively evaluated under dry sliding, blowing air, and simulated sand-dust conditions. The tribological tests were conducted on an improved block-on-ring test rig equipped with an attachment for simulating the sand-dust environment. The reason for the difference in the tribological behavior of these polymers under the three test conditions was also comparatively discussed, based on scanning electron microscopic examination of the worn polymer specimens and counterfaces. Under blowing air conditions, the decrease of the contact temperature produced by blowing air led to the increase in the shearing strength of the sliding surface when compared with dry sliding conditions and hence to cause an increase in the friction coefficient and a remarkable decrease in the wear rate of PTFE and UHMWPE. On the contrary, blowing air produced a decrease in the friction coefficient of PI because of the formation of transfer film on the counterfaces, and an increase in the wear rate, because the blowing air considerably promoted the transfer of PI onto the counterfaces when compared with dry sliding conditions. Both PTFE and UHMWPE registered the lowest wear rate under sanddust conditions, owing to the tribolayer formation on the worn surfaces, while PI exhibited the highest wear rate because no tribolayer was formed during the abrasive wear process.

Friction, wear and surface damage mechanisms of pneumatic clutch actuators

“…This is most likely due to the fact that particles are more easily embedded into the guiding ring than into the lip seal, as observed in earlier work [4]. Wear of the counter surface by particles embedded into PTFE has been observed by Li and Yan [6]. Particles may have been embedded in the lip seal as well.…”

High Performance Polymer Composites: A Role of Transfer Films in Ensuring Tribological Properties—A Review

“…C. Li and F. Yan compared the friction and wear characteristics of PTFE, UHMWPE and PI under DSF, blowing air to simulate sand-dust conditions [ 61 ]. Among the studied polymers, PI had the highest wear resistance in the DSF mode (WR = 0.2 × 10 −5 mm 3 /Nm).…”

An investigation on wear behavior of UHMWPE/carbide composites at elevated temperatures

“…Ultra‐high molecular weight polyethylene (UHMWPE) is widely used in engineering applications especially in frictional systems due to its superior anti‐wear properties 1 . However, recent studies investigated various kinds of fillers in UHMWPE matrix for further development in the wear resistance of this polymer 2–7 .…”

“…Ultra-high molecular weight polyethylene (UHMWPE) is widely used in engineering applications especially in frictional systems due to its superior anti-wear properties. 1 However, recent studies investigated various kinds of fillers in UHMWPE matrix for further development in the wear resistance of this polymer. [2][3][4][5][6][7] Since hard materials are suggested for tribological systems due to their high wear resistance, carbides, oxides, and nitrides come to the forefront as filler materials in the polymeric matrices.…”