Strengthening Mechanisms and Thermal Models of Chemically Incompatible Metals (Mo/W–Cu): A Review

Abstract

Molybdenum (Mo) and tungsten (W) are elements of the same family with similar properties, and both of them have high hardness, mechanical strength, and electrochemical corrosion properties, [1] which are widely used in the research and application of hightemperature and arc ablation-resistant materials. [2,3] Mo-Cu and W-Cu alloys are typical pseudoalloys. [4] There is almost no reaction between tungsten and copper, molybdenum and copper in the sintering process, and almost no intermetallic compounds are produced, which is due to the great differences in crystal structure and physical properties between tungsten and copper particles, molybdenum and copper particles. [5,6] W-Cu alloys and Mo-Cu alloys are widely used in microelectronics applications, aerospace technology, and military equipment because of their excellent electrical conductivity, excellent thermal conductivity, excellent arc resistance, flame retardant of fused joints, and other attractive properties. [1,[7][8][9] The addition of Cu and other high thermal conductivity (TC) metals can make it have a thermal expansion coefficient (CTE) close to silicon and high TC. [7][8][9][10][11][12][13] When the service temperature exceeds the melting point of Cu, Cu in the material can absorb a lot of heat through the transformation of physical states such as liquefaction and evaporation, and play a role of sweating and cooling. [9] As a result, Mo/W-Cu composites (Mo-Cu and W-Cu) have excellent high-temperature resistance and better ablation resistance than pure metal Mo/W. [14][15][16][17] Mo/W-Cu composites have excellent physical and mechanical properties, but their applications are severely limited by density and interface problems. Densification and interface strengthening can improve mechanical, thermal, and electrical properties of Mo/W-Cu composites. The electrical and thermal properties of Mo/W-Cu composites are closely related to the addition of alloying elements, [6] densification of green compacts, [18,19] thermal cycle, [20] and applied pressure in the case of hot pressing. [21] At present, the study in the densification of Mo/W-Cu composites is almost about the influence of a single factor, and there is no comprehensive summary of the densification process. In the experimental process, there are also considerable difficulties in fully characterizing the microstructure, atomic structure, and chemical properties of the interface, which can be described by creating molecular dynamics models. However, there are few researches on molecular dynamics simulation of Mo/W-Cu composite.Mo/W-Cu composites are an attractive radiator material due to their combinational properties of Mo/W and Cu. [22] However, Mo/W-Cu composites materials are widely distributed in

High‐Performance, Multifunctional, and Designable Carbon Fiber Felt Skeleton Epoxy Resin Composites EP/CF‐(CNT/AgBNs)x for Thermal Conductivity and Electromagnetic Interference Shielding

“…Numerous studies have demonstrated that the integration of efficient thermally and electrically conductive carbon‐based fillers, including carbon nanotubes (CNT), [ 6 ] graphene oxide [ 7,8 ] and carbon fiber (CF), [ 9 ] as well as metal‐based fillers such as Cu [ 10 ] and Ag [ 11,12 ] into epoxy resin to establish interconnected networks, which apparently facilitated the movement of phonons and electrons within the epoxy resin, thus boosting its thermal and electrical conductivity. [ 13 ] Especially, CNT exhibit ultrahigh thermal conductivity (TC) from 2800 to 6000 W m −1 K −1 and offer a great advantage in EMI shielding applications on account of their high electrical conductivity.…”