Copper is often used as a heat-dissipating material due to its high thermal conductivity. In order to improve its heat dissipation performance, one of the feasible methods is to compound copper with appropriate reinforcing phases. With excellent thermal properties, graphene has become an ideal reinforcing phase and displays great application prospects in metal matrix composites. However, systematic theoretical research is lacking on the thermal conductivity of the copper–graphene interface and associated affecting factors. Molecular dynamics simulation was used to simulate the interfacial thermal conductivity of copper/graphene composites, and the effects of graphene layer number, atomic structure, matrix length, and graphene vacancy rate on thermal boundary conductance (TBC) were investigated. The results show that TBC decreases with an increase in graphene layers and converges when the number of graphene layers is above five. The atomic structure of the copper matrix affects the TBC, which achieves the highest value with the (011) plane at the interface. The length of the copper matrix has little effect on the TBC. As the vacancy rate is between 0 and 4%, TBC increases with the vacancy rate. Our results present insights for future thermal management optimization based on copper matrix composites.

The interface microzone characteristics determine the thermophysical properties of diamond/Cu composites, while the mechanisms of interface formation and heat transport still need to be revealed. Here, diamond/Cu-B composites with different boron content were prepared by vacuum pressure infiltration. Diamond/Cu-B composites up to 694 W/(mK) were obtained. The interfacial carbides formation process and the enhancement mechanisms of interfacial heat conduction in diamond/Cu-B composites were studied by HRTEM and first-principles calculations. It is demonstrated that boron can diffuse toward the interface region with an energy barrier of 0.87 eV, and these elements are energetically favorable to form the B₄C phase. The calculation of the phonon spectrum proves that the B₄C phonon spectrum is distributed in the range of the copper and diamond phonon spectrum. The overlapping of phonon spectra and the dentate structure together enhance the interface phononic transport efficiency, thereby improving the interface thermal conductance.

As a thermal interface material, diamond/GaInSn composites have wide-ranging application prospects in the thermal management of chips. However, studies on systematic reliability that can guide the practical application of diamond/GaInSn in the high-temperature, high-temperature impact, or high-humidity service environments that are faced by chips remain lacking. In this study, the performance evolution of diamond/GaInSn was studied under high-temperature storage (150 °C), high- and low-temperature cycling (−50 °C to 125 °C), and high temperature and high humidity (85 °C and 85% humidity). The experimental results reveal the failure mechanism of semi-solid composites during high temperature oxidation. It is revealed that core oxidation is the key to the degradation of liquid metal composites’ properties under high-temperature storage and high- and low-temperature cycling conditions. Under the conditions of high temperature and high humidity, the failure of Ga-based liquid metal and its composite materials is significant. Therefore, the material should avoid high-temperature and high-humidity environments.

A series of hetero-binuclear superatom motifs involving chloride/bromide ligands, that is, MM′X₄⁻ (M = Li, Na; M′ = Be, Mg, Ca; X = Cl, Br) anions, have been characterized by using many-body perturbation theory calculations. Large vertical electron detachment energies (VDEs, 5.470–6.799 eV) confirm the superhalogen identity of these anions. A larger VDE value can be obtained by introducing small M or large M′ central atoms and small halogen ligand atoms. Thus, one isomer of LiCaCl₄⁻ possesses the largest VDE value. Besides, when the extra electron is shared by all ligand atoms or three bridging ligand atoms, the isomers have relatively larger VDE values.

The technical problem of copper additive manufacturing is expected to be solved through the size effect of nanomaterials. The molecular dynamics method was employed to understand the laser sintering process of single-crystal copper nanoparticles. Based on a theoretical characterization of the densification of nanocopper sintering developed at present and the prediction of the melting point of nanocopper, the sintering and densification behaviors of copper nanoparticles with different sizes at different sintering temperatures were investigated. It is finally concluded that the densification of the nanocopper sinter can reach up to 95% under the condition of sintering temperature below the melting point of the nanocopper.