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Covalent adaptable networks (CANs), leveraging the dynamic exchange of covalent bonds, emerge as a promising material to address the challenge of irreversible cross‐linking in thermosetting polymers. In this work, we explore the introduction of a catalyst‐free and associative C=C/C=N metathesis reaction into thermosetting polyurethanes, creating CANs with superior stability, solvent resistance, and thermal/mechanical properties. By incorporating this dynamic exchange reaction, stress‐relaxation is significantly accelerated compared to imine‐bond‐only networks, with the rate adjustable by modifying substituents in the ortho position of the dynamic double bonds. The obtained plasticity enables recycle without altering the chemical structure or mechanical properties, and is also found to be vital for achieving shape memory functions with complex spatial structures. This metathesis reaction as a new dynamic crosslinker of polymer networks has the potential to accelerate the ongoing exploration of malleable and functional thermoset polymers. [ABSTRACT FROM AUTHOR]

SiC/Al composites are widely used in aerospace and other fields due to their excellent mechanical properties. For large-concentration composites, due to the extremely high proportion of SiC and the unstable interface between the two phases, the SiC particles are broken and detached during the processing, which makes the surface quality of the workpiece insufficient to meet the service requirements. Electrically assisted cutting technology is expected to break through this technical bottleneck. This paper investigates the surface quality of high-concentration SiC/Al grinding with electroassisted biolubricant MQL. The surface morphology after processing is observed. Firstly, by comparing the traditional grinding and electrically assisted grinding conditions, it is found that the fundamental reason for the improvement in the grinding surface quality using a pulse current is the improvement in the Al plasticity. Secondly, based on the thermal effect and non-thermal effect of the pulse current, the influence of the electrical parameters (current, duty cycle and frequency) on the machining indication quality is discussed. It is found that when the current and duty cycle increase, the machining surface quality will also increase, while the frequency change has little effect on the surface quality. Finally, friction and wear experiments are carried out on the grinding surface under different working conditions to explore the friction and wear characteristics of the surface of the workpiece. The results show that the pulse current can significantly improve the wear resistance of the grinding surface. [ABSTRACT FROM AUTHOR]

Electrostatic atomization minimum quantity lubrication (EMQL) technology has been developed to address the need for environmentally friendly, efficient, and low-damage grinding of challenging titanium alloy materials. EMQL leverages multiple physical fields to achieve precise atomization of micro-lubricants, enabling effective lubrication in high temperature, high pressure, and high-speed grinding environments through the use of electric traction. Notably, the applied electric field not only enhances atomization and lubrication capabilities of micro-lubricants but also significantly impacts heat transfer within the grinding zone. In order to explore the influence mechanism of external electric field on spatial heat transfer, this paper first comparatively analyzes the grinding heat under dry grinding, MQL, and EMQL conditions and explores the intensity of the effect of external electric field on the heat transfer behavior in the grinding zone. Furthermore, the COMSOL numerical calculation platform was used to establish an electric field-enhanced (EHD) heat transfer model, clarifying charged particles' migration rules between poles. By considering the electroviscous effect, the study reveals the evolution of heat transfer structures in the presence of an electric field and its impact on heat transfer mechanisms. [ABSTRACT FROM AUTHOR]