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The dimensional compensation technology can achieve high dense metal parts with precise dimensions for binder jet 3D printing (BJ3DP). In this study, two models (cuboid and gear) of BJ3DP 316L stainless steel (BJ3DP316LSS) parts were established. Numerical simulation and experimental volume shrinkage of the BJ3DP316LSS sintered parts via dimensional compensations technology were investigated. When the dimensional compensation coefficient was set as 1.25, the BJ3DP316LSS cuboids and gears exhibited high densification as 99.6% and 99.4%, respectively. The experimental dimension deviation rates of cuboid and gear parts after dimensional compensations ranged from −3.56% to −0.15% and from 0.89% to 3.42%, respectively. Due to twinning-induced plasticity mechanism, the BJ3DP316LSS sintered gear part via dimensional compensation technology exhibited high hardness (∼139 HV), high yield strength (∼249 MPa), high ultimate tensile strength (∼546 MPa) and excellent elongation (∼62%), which are higher than those of the reported 316LSS samples.

Solute atoms and second phases with low thermal conductivity are habitually regarded as the factors to the thermal conductivity of alloys. Nevertheless, the interface that is usually neglected can also be a noteworthy factor influencing the thermal conductivity of alloys due to its inherent nature of defects. The effect of interface on the thermal conductivity of alloys was quantitatively scrutinized in the binary Mg–La, Mg–Ce, Mg–Sm, Mg–Al, Mg–Zn, and Mg–Si alloys with concentration gradients. The effect of diverse excess second phases on the deterioration of thermal conductivity for Mg alloys followed this order: Mg2Si＞Mg17Al12＞Mg17La2＞Mg12Ce＞Mg41Sm5＞MgZn2. The quantitative total interfacial thermal resistance model for alloys was proposed, which was quantitatively understood by R=AGsρs3+BGsρs+CGs3ρs. The sequence of experimental data was conformed to that of the theoretical data acquired by this model. Alloying elements which second phases possess low shear modulus (G) and high density (ρ) were beneficial for the development of the low-thermal-resistance alloys. This rule can reinforce the theoretical basis for the thermal conduction of alloys. The data of the total interfacial thermal resistance was established preliminarily to instruct the design of low-thermal-resistance and high-thermal-conductivity Mg alloys.

Herein, graphene with two different average sheet diameters was ultrasonically dispersed, mechanically stirred, and copper-plated. The pretreated graphene was mixed with 6061-aluminum (6061Al) powder to fabricate copper-plated graphene (0.5 wt%) reinforced 6061Al matrix composites by spark plasma sintering. The resulting composites were characterized in terms of their microstructure, tensile properties, electrical conductivity, and thermal conductivity. The incorporation of graphene facilitated load transfer and hindered dislocation movement, thereby enhancing the mechanical properties of the composites. Notably, the composite reinforced by larger-sized graphene achieved a favorable combination of high tensile strength (218 MPa) and fracture strain (17.2 %). Moreover, the addition of graphene also ameliorated the electrical conductivity of 6061Al. The composite reinforced by the larger-sized graphene achieved the highest electrical conductivity of 47.7 %IACS, attributed to the formation of a wider range of conductive channels. Additionally, the introduction of larger-sized graphene increased the thermal conductivity of 6061Al from 161.4 W/(m·K) to 183.2 W/(m·K), whilst the smaller-sized graphene contributed to a modest enhancement of 15.3 W/(m·K). In conclusion, graphene with a larger sheet diameter exhibits a remarkable reinforcement effect on the overall performance of 6061Al.