This study utilizes FeCoCrNiAl itself as the Ni source to grow the Shandite phase Ni₃Sn₂S₂ in situ on its surface. By constructing Ni₃Sn₂S₂@FeCoCrNiAl with heterogeneous interfaces and continuous nanocoating, further modulated interfacial charge transfer and d-p hybridization while integrating the thermal conduction network. This approach simultaneously enhanced microwave absorption and thermal conductivity, balancing the opposing effects of interfacial phenomena on phonon heat transfer and microwave absorption. Multi-scale characterization techniques confirm the formation of crystalline phases and the achievement of dense, uniform coating, with increasing content leading to more uniform and dense coatings. The synergistic effect between dielectric loss based on Ni₃Sn₂S₂ and magnetic loss from high-entropy alloys achieves a minimum reflection loss (RL_min) of -44.26 dB. After introducing FSS, the thickness is optimized to 1.4 mm, further reducing RL_min to -60.47 dB. Regarding thermal conductivity, the 30 wt% silicone rubber composite sample achieved a ΔT = 104.3 °C temperature rise within 8 s. Density Functional Theory calculations reveal that transition metal d orbitals (Fe/Co/Ni, including Ni at the Ni₃Sn₂S₂ side) overlap with S-3p orbitals at the interface, forming d-p hybridization and creating a more continuous conductive state. The plane-averaged differential charge density reveals an interfacial dipole layer of approximately 1.2 Å (peaking at 6.53 and 7.71 Å), indicating electron migration from HEA to Ni₃Sn₂S₂. This leads to interfacial polarization and enhanced dielectric loss. The aforementioned electronic structural evidence aligns with macroscopic testing, providing new ideas for developing multifunctional microwave absorption and thermal conductivity materials.

In the power plant boiler industry, dissimilar steel welding is widely used in the connection of thermal power generation units. As an important component of the unit, research on the organizational properties of dissimilar steel welded joints has significant guidance for the life design of the joint. For the long-term service state of TP304H/T22 dissimilar steel welded joints, the microstructure’s morphological evolution, the microhardness, and the tensile properties of tube samples were analyzed using tests and numerical simulations. The results show that the microstructure of each part of the welded joint was free of damaged features, such as a creep cavity and intergranular cracks. The microhardness of the weld was higher than that of the base metal. In the tensile test, the welded joints broke at the weld metal at room temperature and at the side of the TP304H base metal at a temperature of 550 °C. The tensile fracture morphology demonstrated a change from a ductile fracture to a hybrid fracture when the temperature rose. The fusion zone and base metal on the TP304H side were the stress concentration areas of the welded joint, which easily sprouted cracks. This study holds significant reference value in assessing the safety and reliability of dissimilar steel welded joints in superheater units.

In this paper, a Wiener filtering algorithm in the wavelet domain is proposed to filter the laser self-mixing interference (SMI) signals, which is used to improve the accuracy of displacement reconstruction. The Wiener filter is theoretically constructed and applied to filter both high-frequency coefficients and low-frequency coefficients in the wavelet domain, which are obtained by two-level discrete wavelet transformation (DWT) decomposition from unfiltered SMI signals. Two-level wavelet decomposition in wavelet threshold filtering is determined without any manual judgment. Subsequently, the inverse DWT is employed to generate the filtered SMI signals. Compared with that, using wavelet threshold denoising, the results of the simulation and experiments demonstrate that the displacement reconstruction from the filtered SMI signals exhibits better accuracy when using Wiener filtering in the wavelet domain with two levels of wavelet decomposition. Also, the fake peaks due to local oscillation caused by wavelet threshold filtering can be eliminated effectively. The proposed method employs two-level wavelet decomposition, ensuring computational efficiency and achieving an 11.3% improvement in displacement reconstruction accuracy compared to wavelet threshold filtering. The maximum error ratio of the micro-displacement reconstruction is reduced to 2.7% using the Wiener filter in the wavelet domain.

Developing Cu-based composites with excellent electrical and mechanical properties under multiphysics-coupled service conditions remains challenging. Novel Cu-Nb-Gr composites were fabricated by high-energy ball milling and High-pressure Multi-field Assisted Rapid Sintering. Experiments combined with computational fluid dynamics (CFD) and finite element method (FEM) simulations were used to investigate how Gr regulates material performance. The incorporation of 3 vol.% Gr promoted the formation of a semi-continuous Gr-rich structure coupled with an Nb-rich load-bearing structure. Under arc erosion, the semi-continuous Gr-rich structure provided efficient heat-conduction pathways, reducing the peak temperature and metal-vapor recoil force, while the Nb-rich load-bearing structure suppressed liquid–metal spattering and stabilized the molten pool. Simultaneously, Gr dynamically spread to form a continuous solid-lubricating film during sliding friction, significantly reducing the coefficient of friction and interfacial shear stress. Furthermore, under compressive loading, the semi-continuous Gr-rich structure coupled with the Nb-rich load-bearing structure alleviated interfacial elastic–modulus mismatch and extreme stress concentration, limiting macroscopic plastic deformation of the matrix. Consequently, Cu-Nb-3Gr achieved a favorable balance of arc-erosion resistance, wear resistance, and compressive performance, providing a new strategy for improving conventional Cu-based composites.