Abstract
The structure, mechanical and tribological properties of the polyimide-based composites reinforced with chopped carbon fibers (CCF) and loaded with solid-lubricant commercially available fillers of various natures were investigated. The metal- and ceramic counterparts were employed for tribological testing. Micron sized powders of PTFE, colloidal graphite and molybdenum disulfide were used for solid lubrication. It was shown that elastic modulus was enhanced by up to 2.5 times, while ultimate tensile strength was increased by up 1.5 times. The scheme and tribological loading conditions exerted the great effect on wear resistance of the composites. In the tribological tests by the ‘pin-on-disk’ scheme, wear rate decreased down to ~290 times for the metal-polymer tribological contact and to ~285 times for the ceramic-polymer one (compared to those for neat PI). In the tribological tests against the rougher counterpart (Ra~0.2 μm, the ‘block-on-ring’ scheme) three-component composites with both graphite and MoS2 exhibited high wear resistance. Under the “block-on-ring” scheme, the possibility of the transfer film formation was minimized, since the large-area counterpart slid against the ‘non-renewable’ surface of the polymer composite (at a ‘shortage’ of solid lubricant particles). On the other hand, graphite and MoS2 particles served as reinforcing inclusions. Finally, numerical simulation of the tribological test according to the ‘block-on-ring’ scheme was carried out. Within the framework of the implemented model, the counterpart roughness level exerted the significantly greater effect on wear rate in contrast to the porosity.
Highlights
Introduction iationsPolyimides (PI) are high-tech plastics with excellent mechanical properties, including at elevated temperatures
We investigated the mechanical and tribological characteristics of two- and threecomponent PI-based composites loaded with PTFE and chopped carbon fiber (CF) (CCF, 200 μm in length) at different load-speed (P·V) modes according to the ‘pin-on-disk’ scheme [32]
Analysis the results enabled to conclude thatthat the the PI/10CCF/10PTFE
Summary
Polyimides (PI) are high-tech plastics with excellent mechanical properties, including at elevated temperatures. This enables their use for manufacturing polymer composites [1,2,3,4,5,6]. Neat PI is rarely used for the fabrication of parts for tribological units, since it is characterized by a rather high wear rate under dry sliding friction conditions [11,12]. To solve this issue, a number of solid lubricant fillers are loaded for reducing its wear rate and the friction coefficient in tribological contacts.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
