Organic-inorganic hybrid coating films have been used to increase the transmittance and enhance the physical properties of plastic substrates. Sol-gel organic-inorganic thin films were fabricated on polymethylmethacrylate (PMMA) substrates using a dip coater. Metal alkoxide precursor tetraethylsilicate (TEOS) and alkoxy silanes including decyltrimethoxysilane (DTMS), 3-glycidoxypropyltrimethoxysilane (GPTMS), phenyltrimethoxysilane (PTMS), 3-(trimethoxysilyl)propyl methacrylate (TMSPM) and vinyltrimethoxysilane (VTMS) were used to synthesize sol-gel hybrid coating solutions. Sol-gel synthesis was confirmed by the results of FT-IR. Cross-linking of the Si-O-Si network during synthesis of the sol-gel reaction was confirmed. The effects of each alkoxy silane on the coating film properties were investigated. All of the organicinorganic hybrid coatings showed improved transmittance of over 90 %. The surface hardness of all coating films on the PMMA substrate was measured to be 4H or higher and the average thickness of the coating films was measured to be about 500 nm. Notably, the TEOS/DTMS coating film showed excellent hydrophobic properties, of about 97°.

In this paper, we aim to improve the output quality of a food 3D printer through optimized component design and implementation. Existing 3D printers produce customized outputs according to consumer needs, but have problems with output speed and poor quality. In this paper, we aim to solve this problem through optimized design of unit parts such as the extruder, nozzle, guide, and external case. Fusion 360 was used for element design, and in the performance evaluation of the implemented system, the average precision was 0.06mm, which is higher than the non-repeatable precision of ±0.1㎜ of other products, and the feed speed of the existing system was evaluated to be more than twice as fast, from 70mm/s to 140mm/s. In the future, we plan to continuously research output elements that can produce texture and color and device control methods for convenience.

In this paper, the goal is to produce a target wheel that integrates the plate and CPS wheel among the components of the drive plate mounted on an automobile engine. We attempted to develop a manufacturing process technology for incremental forming of a target wheel with the desired thickness by rotating a disk-shaped thin plate material and deforming the plate using a forming device and tools. Incremental forming system was set up by establishing a forming process and designing and manufacturing the device and parts required for processing. It consists of a total of 4 stages of molding process, and the optimal roll design that can properly collect materials to prevent cracks or reverse steps at each stage is primarily important. After manufacturing the prototype, a material test was performed to confirm whether the mechanical properties of the deformed part were sufficient to make gear teeth.

In response to the global interest and efforts towards reducing plastic use and promoting resource recycling, there is a growing need to establish methods for recycling discarded fishing gear. In Korea, various technologies are being developed to recycle discarded fishing gear, but significant technical and policy challenges still remain. In particular, biodegradable gill nets require a pre-treatment process to separate biodegradable materials from other substances and to remove salt before recycling. Therefore, this study aims to develop a pre-treatment device for recycling biodegradable gill nets and to evaluate the feasibility of recycling them.

High-entropy alloys (HEAs) have been reported to have better properties than conventional materials; however, they are more expensive due to the high cost of their main components. Therefore, research is needed to reduce manufacturing costs. In this study, CoCrFeMnNi HEAs were prepared using metal injection molding (MIM), which is a powder metallurgy process that involves less material waste than machining process. Although the MIM-processed samples were in the face-centered cubic (FCC) phase, porosity remained after sintering at 1200°C, 1250°C, and 1275°C. In this study, the hot isostatic pressing (HIP) process, which considers both temperature (1150°C) and pressure (150 MPa), was adopted to improve the quality of the MIM samples. Although the hardness of the HIP-treated samples decreased slightly and the Mn composition was significantly reduced, the process effectively eliminated many pores that remained after the 1275°C MIM process. The HIP process can improve the quality of the alloy.

Additive Manufacturing (AM) is a process that fabricates products by manufacturing materials according to a three-dimensional model. It has recently gained attention due to its environmental advantages, including reduced energy consumption and high material utilization rates. However, controlling defects such as melting issues and residual stress, which can occur during metal additive manufacturing, poses a challenge. The trial-and-error verification of these defects is both time-consuming and costly. Consequently, efforts have been made to develop phenomenological models that understand the influence of process variables on defects, and mechanical/ electrical/thermal properties of geometrically complex products. This paper introduces modeling techniques that can simulate the powder additive manufacturing process. The focus is on representative metal additive manufacturing processes such as Powder Bed Fusion (PBF), Direct Energy Deposition (DED), and Binder Jetting (BJ) method. To calculate thermal-stress history and the resulting deformations, modeling techniques based on Finite Element Method (FEM) are generally utilized. For simulating the movements and packing behavior of powders during powder classification, modeling techniques based on Discrete Element Method (DEM) are employed. Additionally, to simulate sintering and microstructural changes, techniques such as Monte Carlo (MC), Molecular Dynamics (MD), and Phase Field Modeling (PFM) are predominantly used.

The growing significance of sustainable energy technologies underscores the need for safe and efficient management of spent nuclear fuels (SNFs), particularly via deep geological disposal (DGD). DGD involves the long-term isolation of SNFs from the biosphere to ensure public safety and environmental protection, necessitating materials with high corrosion resistance for DGD canisters. This study investigated the feasibility of a Cu–Ni film, fabricated via additive manufacturing (AM), as a corrosion-resistant layer for DGD canister applications. A wire-fed AM technique was used to deposit a millimeter-scale Cu–Ni film onto a carbon steel (CS) substrate. Electrochemical analyses were conducted using aerated groundwater from the KAERI underground research tunnel (KURT) as an electrolyte with an NaCl additive to characterize the oxic corrosion behavior of the Cu–Ni film. The results demonstrated that the AM-fabricated Cu–Ni film exhibited enhanced corrosion resistance (manifested as lower corrosion current density and formation of a dense passive layer) in an NaCl-supplemented groundwater solution. Extensive investigations are necessary to elucidate microstructural performance, mechanical properties, and corrosion resistance in the presence of various corroding agents to simplify the implementation of this technology for DGD canisters.

This study introduces a novel approach for identifying potential failure risks in missile manufacturing by leveraging Quality Inspection Management (QIM) data to address the challenges presented by a dataset comprising 666 variables and data imbalances. The utilization of the SMOTE for data augmentation and Lasso Regression for dimensionality reduction, followed by the application of a Random Forest model, results in a 99.40% accuracy rate in classifying missiles with a high likelihood of failure. Such measures enable the preemptive identification of missiles at a heightened risk of failure, thereby mitigating the risk of field failures and enhancing missile life. The integration of Lasso Regression and Random Forest is employed to pinpoint critical variables and test items that significantly impact failure, with a particular emphasis on variables related to performance and connection resistance. Moreover, the research highlights the potential for broadening the scope of data-driven decision-making within quality control systems, including the refinement of maintenance strategies and the adjustment of control limits for essential test items.

The objective of this study is to identify the priority of elements for effective implementation of MES in small and medium-sized manufacturing enterprises trying to develop into smart factories. For this purpose, the Delphi method and the Analytic Hierarchy Process(AHP) mothod are applied. As a result of the study, the cooperation of the members in the supply chain is the most important factor for small and medium-sized enterprises in order to survive in the global competitive environment. Therefore, the enterprises need to make various efforts to create synergies through the technical strength of suppliers and the cooperation in the process of introducing and operating MES.

우리나라 제조 소기업은 온실가스 고배출 업종이 많고, 산재사망사고 발생 비중이 높아 수출의존도가 높은 국내 제조 소기업에 대한 ESG 이슈 관리가 점차 중요해 질 것이다. 본 연구는 제조 소기업의 저탄소 활동이 현장 작업자의 안전의식과 산업재해에 미치는 영향을 파악하고, 저탄소 활동이 안전, 고용 등의 영역에서 발생하는 부정적 영향을 감소 시켜 기업의 경쟁력을 향상시킬 수 있는 방안을 모색해 보았다. 연구에서는 제조 소기업의 저탄소 활동(저탄소 전략 및 시스템 활동, 온실가스 및 환경오염 분야 활동, 자원 및 에너 지 분야 활동)이 산업안전 인식 향상에 긍정적(+)인 영향을 미치는 것을 확인하고, 저탄소 활동에 참여한 기업들의 산업재해율이 감소하였으며, 매출과 고용이 증가하는 성과가 나 타난 것을 확인하였다. 따라서 정부는 제조 소기업의 저탄소 활동과 산업안전, 고용창출이 연계될 수 있도록 정책적인 지원을 통해 지속가능한 성장을 위한 핵심 경영 전략으로 자리 잡게 해야 한다.