Microstructural, mechanical, and tribological properties of a novel hybrid LLDPE/PTFE/x wt.% GNPs for bearing surface applications

• Published in: Journal of mechanical science and technology 2024, 38(1), , pp.163-175
• Main Authors: Hassan, A. El-Sayed M., Abu-Oqail, A. M. I., Abu-Okail, Mohamed
• Format: Article
• Language: English
• Subjects: Control; Dynamical Systems; Engineering; Fractions; Frictional wear; Hot pressing; Industrial and Production Engineering; Mechanical Engineering; Mechanical properties; Microhardness; Modulus of elasticity; Nanocomposites; Original Article; Overheating; Polytetrafluoroethylene; Pressure molding; Sliding friction; Tribology; Vibration; Wear rate; 기계공학
• ISSN: 1738-494X; 1976-3824
• DOI: 10.1007/s12206-023-1214-y

This study presents a novel nanocomposite of LLDPE/15 wt.% PTFE/1 wt.% GNPs by using a hot compression molding technique to increase its compatibility with harsh operations in bearing surface applications. From an industrial perspective, various problems occur in bearing surface applications during running, particularly an overheating problem. Therefore, the major objective of this study is to synthesize LLDPE by mixing a dual matrix of LLDPE/x wt.% PTFE with different weight fractions of PTFE (from 0 wt.% up to 20 wt.%) and then incorporating the optimum case of a dual matrix with different weight fractions of GNPs (from 0 wt.% up to 1.5 wt.%) to improve mechanical and tribological properties. SEM was used to describe microstructural observations of the prepared nanocomposites. Compression and microhardness tests were performed to investigate the mechanical properties. Dry sliding wear and COF tests were implemented by pin-on-disc with a load cell to examine the tribological characteristics. Microstructural observations of LLDPE/15 wt.% PTFE elucidate good mixing compared to pure LLDPE samples. In addition, observations of morphological properties show ideal mixing and adhesion between LLDPE/15 wt.% PTFE and 1 wt.% GNPs, which eliminate defects and cause a strengthening mechanism between matrix and reinforcement. Elastic modulus and microhardness of LLDPE/15 wt.% PTFE were improved by 73.77 % and 41.39 %, respectively, compared to pure LLDPE samples. Moreover, the wear rate and COF of LLDPE/15 wt.% PTFE composites were enhanced by 72.41 and 7.04 %, respectively, compared to pure LLDPE. Moreover, after adding 1 wt.% of GNPs to LLDPE/15 wt.% PTFE, elastic modulus, microhardness, wear rate, and COF were improved by 16.15 %, 27.47 %, 29.73 %, and 45.24 %, respectively, compared to the unfilled dual matrix of LLDPE/15 wt.% PTFE.