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The tribological properties of materials exhibit a complex and non-linear correlation under varying operational conditions. Therefore, prioritizing a data-driven approach to predict service capability for accelerating material design and preparation is imperative in advancing tribology. The investigation was conducted to analyze the tribological performance and wear mechanism of PTFE composites. The machine learning (ML) approach was concurrently employed to predict tribological properties under diverse operational conditions. The gradient boosting regression (GBR) model demonstrated excellent predictive performance, with R2 of 82% and 91% for the friction coefficient and wear rate, respectively. Furthermore, Pearson correlation coefficient indicated that temperature and speed has a greater impact on friction coefficient and wear rate when compared to load. • The gradient boosting regression (GBR) model demonstrated outstanding predictive performance. • Pearson correlation coefficient indicated that temperature and speed had a greater impact. • With the increase in speed, the friction coefficient and wear rate exhibited a decreasing trend. [ABSTRACT FROM AUTHOR]

The friction coefficients of composites prepared by traditional fillers and structure design are usually uncontrollable, which gradually cannot meet the requirements of intelligent response behavior in the modern manufacturing industry. Hence, an epoxy, graphene oxide, and paraffin wax composite (GPEP@ PW) with a network-like sandwich structure was prepared by a four-step method (template method-vacuum impregnation-de-template-vacuum impregnation). Due to sensitive photothermal conversion of GO and excellent ability to control heat (absorption and release) of paraffin wax, GPEP@ PW can respond to near-infrared light to realize the real-time conversion of friction coefficient (0.052 and 0.062), while the wear rate was reduced by two orders of magnitude rate (10−4 to 10−6 mm3/N·m). The light response behavior of tribology under different near-infrared intensities was studied. This strategy is simple and versatile, providing a new idea for the design and preparation of light stimulus-responsive materials to achieve smart tribological properties. [Display omitted] • Ternary hybrid composite with 3D sandwich structure was prepared by a four-step method. • Real-time controllable friction was achieving by structural functionalized photothermal conversion of GO. • The COF changed between 0.052 and 0.062 with NIR switching on and off. • Extremely low wear rate (3.33 × 10−6 mm3/N.m) was got by synergy in GO and paraffin wax. [ABSTRACT FROM AUTHOR]

Two ways to enhance conversion efficiency of the ultrasonic motor (USM) were developed. According to mechanical and tribological properties, an advanced polyimide (PI) friction material was fabricated. In comparison to conventional polytetraflfluoroethylene (PTFE) friction material, the novel PI friction material enhanced efficiency from 29% to 44%, an improvement of 51.7%. The results indicated high friction coefficient and high elastic modulus were essential for improving efficiency. Inspired by the unique topography, the micro-dimples were introduced into PI friction material which improved the efficiency from 44% to 53%, an increment of 20.5%. The optimum parameter was diameter of 200 μm and area density of 7%. The effect of surface texture on tribological behavior and output characteristic of the USM was comprehensively explored. • The advanced PI friction material and the surface texture enhance efficiency from 29% to 53%, an increase of 82.8%. • High friction coefficient and high elastic modulus are the main reason for improving the conversion efficiency of the USM. • The surface texture enhance the efficiency of the USM because of increased tangential frictional force. [ABSTRACT FROM AUTHOR]

The poor interfacial compatibility between functional fillers and matrix greatly restricts development of polymer composites. Therefore, in the present paper, carbon fibers (CFs) were modified by biomimetic polydopamine (PDA) and amino silane (KH550) to improve interfacial bonding strength with epoxy (EP) substrate. The grafting of PDA and KH550 was divided into "PDA", "PDA-KH550" and "(PDA + KH550)" methods for regulating interfacial compatibility and exploring the reaction mechanism. Improved interfacial strength was beneficial to transfer stress from the matrix to fillers. Consequently, mechanical properties of modified CF/EP were obviously superior to those of unmodified EP/CF. Besides, wear resistance of EP/CF-(PDA + KH550) had an increase of 76%, 67%, 60% and 49% compared to that of EP, CF/EP, CF-PDA/EP and EP/CF-PDA-KH550. Image 1 • PDA and KH550 were used to regulate interfacial compatibility of CF and EP. • The different reaction mechanisms of PDA and KH550 were explored. • The tribological mechanism of modified CF/EP were systematically analyzed. • "CF-(PDA + KH550)" method significantly improved simultaneously the mechanical properties and wear resistance. [ABSTRACT FROM AUTHOR]