This study investigates the impact of asynchronous rolling on the microstructure, tensile properties, and electrical conductivity of pure copper. Pure copper sheets were subjected to asynchronous rolling with asynchronous ratios of 1.0 and 1.2, followed by microstructural analysis using electron backscatter diffraction, tensile testing, and resistivity measurements. Notable increases in ultimate tensile strength and yield strength were observed, with the sample processed at an asynchronous ratio of 1.2 showing improvements of 25.8% in tensile strength and 3.42% in yield strength compared to the sample processed at an asynchronous ratio of 1. However, an increase in strain localization and a decrease in elongation were noted, indicating a trade-off between strength and ductility. Furthermore, conductivity measurements revealed that the increase in asynchronous ratio led to a rise in defect density, resulting in a 19.96% decrease in conductivity. These findings provide valuable insights into optimizing asynchronous rolling parameters to tailor the performance of pure copper in various industrial applications.

Composite-to-metal interference-fit is widely used in the aerospace field, where the problem of the damage and failure of composite materials is particularly critical. A numerical study was conducted on the damage and failure of carbon fiber composite sleeves with multiple structural parameters during interference-fit assembly. ABAQUS/Explicit simulation of interference-fit was performed with the three-dimensional finite element method, and the VUMAT subroutine with three-dimensional Hashin damage was utilized to investigate the initiation and evolution of composite component damage. The effects of different relative wall thicknesses and layup sequences on the selection of maximum interference were analyzed. The results reveal that the stress distribution on the inner surface of the sleeve is more uniform with the condition of radial layup. Radial layup enables 0.2% interference at 25% wall thickness, a 100% increase over axial layup. This study contributes to addressing long-standing issues in the aerospace field, such as connection failure and insufficient fatigue life. It is of great significance for improving structural performance, reducing costs, and promoting technological innovation.

To investigate the influence of substrate curvature and process deviations on the bonding quality of microchips mounted on curved surfaces, a thermo–mechanical coupled finite element model was developed in ANSYS 19.2 using a 0402 microchip as a representative component. The model was employed to evaluate the effects of substrate curvature radius, chip placement position, chip angular misalignment, and thermocompression-head angular deviation on the stress distribution and bonding behavior during conformal assembly. The simulation results were further validated through thermocompression bonding experiments. The results show that decreasing the substrate curvature radius significantly increases the stress concentration in the chip-pad region and leads to a more non-uniform stress distribution. In addition, placement errors and loading-direction deviations adversely affect bonding quality by altering the contact stress distribution and increasing the tendency for chip displacement and sliding. Quantitative analysis reveals the relative sensitivity of bonding performance to different geometric and process parameters, providing insight into the dominant thermo–mechanical mechanisms governing curved-surface assembly. Experimental results further demonstrate that excessive thermocompression tilt angles can significantly reduce bonding strength and increase chip sliding, suggesting that the tilt angle should be controlled within an appropriate range to ensure assembly reliability. The proposed thermo–mechanical modeling approach provides a quantitative tool for evaluating the influence of process variations on curved-surface microchip assembly and offers practical guidance for process parameter selection, tolerance control, and reliability-oriented design of conformal electronic packaging.