This paper studies paint removal using laser technology. A finite element model was created using COMSOL Multiphysics software, and the temperature field generated during the cleaning process was analyzed and verified. Laser paint removal behavior was investigated using a fiber laser, and its mechanism studied by combining Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. In-depth analysis of this relatively new technology could provide the theoretical basis for industrial application. The results of this study show that, when compared to the original paint layer, the infrared absorption spectrum of the cleaned surface had two additional two peaks—1333.36 cm⁻¹ and 678.82 cm⁻¹. In addition, there was a decrease in C element content on the treated surface and an increase in O content. In addition, new organic and complex compounds were formed on the cleaned surface as a result of bond cleavage and rearrangement. Furthermore, paint particles of varying sizes and shapes were produced by the impact of plasma shock. Under high-energy laser irradiation, the paint layer underwent combustion, resulting in spherical nanoparticles of uniform shape.

A pulse laser with a wavelength of 1064 nm and a pulse width of 1 µs was used to experiment on the coating of a 2024 aluminum alloy surface. The removal performance of the pulse laser cleaning coating was explored by a single factor analysis and orthogonally conditions, and the effects of the laser power, scanning speed, and pulse frequency on the quality of laser coating removal were summarized. The mechanisms of pulse laser cleaning the coating were studied. The results show that the three parameters of the laser power, scanning speed, and pulse frequency have different effects on the quality of laser coating removal. Among them, with the increase of the scanning speed and pulse frequency, the quality of laser cleaning first increases and then decreases, respectively. With the increase in laser power, the quality of laser cleaning increases. A good laser cleaning quality can be achieved at the laser power of 16.5 W, a scanning speed of 600 mm/s, and a pulse frequency of 30 kHz. The laser cleaning coating involves a variety of mechanisms such as combustion, explosion, gasification, thermal vibration stripping, and laser plasma impact. The result can provide practical references for a better searching of the paint removal.

Extreme high-speed laser cladding (EHLC, Extreme High-Speed Laser Cladding) has attracted attention in material surface modification, due to its high energy density (3 kW/cm²), high deposition rates (20–500 m/min), and notable coating performance. However, the rapid heating and cooling inherent to EHLC can introduce stress concentrations within the coating, resulting in defects such as cracks and porosity that may degrade performance. Process optimization is essential for minimizing these defects and advancing coating quality. This paper reviews current research in EHLC technology, beginning with an overview of its fundamental principles and criteria for cladding material selection, including powder characteristics. The effects of processing parameters, such as laser power, scanning speed, and overlap ratio, on coating quality are analyzed alongside established optimization methods. The influence of external field-assisted technologies on coating properties and their mechanisms for regulating microstructures have been discussed. Finally, future trends in EHLC optimization are identified, with the goal of supporting broader adoption in material modification.

Electromagnetic wave absorption (EWA) aerogels combine high porosity and large specific surface area, which reduce the effective dielectric constant and improve impedance matching, thereby enhancing EWA capability. However, most reported fabrication strategies rely on complex processes such as supercritical drying or freeze-drying, hindering large-scale production. Achieving both high EWA performance and scalable production remains challenging. Herein, we select carbon nanotubes (CNTs) as the dielectric loss phase, nickel ferrite (NiFe₂O₄) as the magnetic loss phase, and cellulose nanofibers (CNFs) as the skeleton to assemble a novelty CNT/NiFe₂O₄/CNF (CNC) aerogel through simple solvent exchange, ion crosslinking, and ambient pressure drying. Solvent exchange and Ca²⁺ coordination with carboxyl groups of CNFs and CNTs suppress capillary-induced structural collapse and maintain the porous network of the CNC aerogel during ambient drying. The introduction of CNTs enhances the conductive network and interfacial polarization, while maintaining favourable impedance matching. As the content of CNTs increases, the dielectric constant gradually rises, while the magnetic loss remained stable. The optimized CNC aerogel achieves the reflection loss of -55.62 dB at the frequency of 6.42 GHz with a matching thickness of 2.80 mm, and an effective absorption bandwidth that covers 10.65 GHz at a thickness of 1.53 mm. Radar cross-section simulations further confirmed its potential for practical EWA applications. The assembly strategy provides a scalable route to lightweight, broadband EWA aerogels.

This study investigates the impact of voltage on the microstructure and corrosion resistance of AZ31B magnesium alloy micro-arc oxidation (MAO) coating. Coatings were prepared at voltages of 300 V, 350 V, 400 V, and 450 V, and their performance was systematically analyzed using scanning electron microscopy (SEM), X-ray diffraction (XRD), electrochemical testing, contact angle measurement, and hardness testing. The findings reveal that as the voltage increases, the coating thickness initially increases before stabilizing, while the surface porosity decreases initially but increases subsequently. The lowest porosity and highest compactness are observed at 350 V. The primary phases of the coating are MgO and Mg₂SiO₄, with higher voltage promoting the formation of MgO. Hardness and roughness exhibit an initial increase followed by a decrease. Electrochemical tests indicate that the 350 V coating has the lowest corrosion current density, the highest impedance modulus, and the best corrosion resistance. Excessive voltage leads to crack formation on the coating surface, compromising its integrity and corrosion resistance. The study concludes that 350 V optimizes the compactness, phase composition, and surface morphology of the coating, thereby enhancing its corrosion resistance. This provides experimental evidence for optimizing surface protection processes for magnesium alloys.