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In the OLED display manufacturing process, a fine metal mask (FMM) is used for the RGB side-by-side in precise positions. An Invar alloy with exceptionally low thermal expansion was used as the FMM material to prevent the deformation of the FMM by heat during the deposition process. The thickness of the FMM must be reduced to less than 10 microns to manufacture high-resolution OLED displays, making it essential to apply a bottom-up electrodeposition process. Moreover, controlling the interfacial energy of the cathode substrate and the electrolyte is necessary to achieve ion electrodeposition and peeling of the ultra-thin Fe-Ni plated on the cathode substrate during electrodeposition. Therefore, this study investigated the effect on the properties of the electrodeposited Fe-Ni alloy by controlling the amount of SLS content, which acts as a surfactant. The amount of SLS content was maintained in the range of 0 to 1 g/L, and the composition homogeneity, microstructure, and surface defects of the electrodeposited Fe-Ni alloy were investigated. Under low pH conditions, the composition was insignificantly changed depending on the difference in the amount of SLS content, and a uniform composition was observed. The findings of this research offer valuable insights for optimizing the electrodeposition process, which is crucial for producing high-resolution OLED displays with ultra-thin FMM, advancing display technology. [ABSTRACT FROM AUTHOR]

Carbon nano-materials are widely used as reinforcing materials for aluminum-based composites due to their excellent metallurgical properties. This study presents an approach for manufacturing Al/C composites utilizing a high energy ball milling and laser powder bed fusion (LPBF) process. We prepared Al/C60 and Al/MWCNT composites under 25 different conditions to observe their microstructure and mechanical property trends according to laser power and scan speed. The relative density of LPBFed composites increased as the energy density increased due to the oxide layer present on the aluminum surface and the high laser reflectance. It was found that, as the energy density increased, the increase in nanohardness and elastic modulus of the LPBFed composites was due to the high relative density. However, the high laser power condition of 179 W resulted in the softening of materials due to grain coarsening, resulting in a decrease in nanohardness and elastic modulus. Under the same laser conditions, the nanohardness of the LPBFed Al/2 vol.% MWCNT composites was approximately 0.5 GPa higher than that of the LPBFed Al/1 vol.% C60 composites, which is explained by the high relative density and grain refinement strengthening. [ABSTRACT FROM AUTHOR]

Abstract: In the present work, we investigate the effects of the size and volumetric fraction of Zr2Cu on the density and mechanical strength of liquid-reactive sintered W/MWCNTs/ Zr2Cu composites. Composite powders are formed by mechanical ball-milling and are sintered into a high density composite at 1400°C. During sintering, two major reactions occur: 1) C atoms in the MWCNTs reacted with the W matrix to form WC; 2) Zr in the Zr2Cu liquid phase, which flows through the capillaries between particles, reacts with WC in the W matrix to form ZrC. Based on our results, higher density composites with finer ZrC reinforcements are successfully produced using sub-micron size Zr2Cu powders. In addition, the amount of Zr2Cu is varied, and the optimal volumetric fraction of Zr2Cu that maximizes the hardness of the composite (1180Hv) is equal to 30vol.%. When the Zr2Cu content is less than the critical value, and the density of the composite is too low due to an insufficient amount of liquid. The hardness of the composite decreases when the Zr2Cu content is greater than 30vol.%, because excess liquid yields a network structure of WC, ZrC, and Zr. The experimental results also reveal that the sintering time required to reach the maximum hardness (1180Hv) significantly decreases as the size of Zr2Cu is reduced from micron-scale to nano-scale. [Copyright &y& Elsevier]