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In micro-/nano-scale, multi-material three-dimensional (3D), structuring has been a major research area for making various applications. To overcome dimensional and material limitations, several hybrid processes have been proposed. The hybrid processes were performed in the same or different numerically controlled stages. If the stages differed, the substrate was moved and locked to the stage before fabrication. During the locking, alignment error occurred. This error became problematic because this significantly compromised the quality of final structures. Here, an alignment method for a hybrid process consisted of a focused ion beam milling, aerodynamically focused nanoparticle printing, and micro-machining was developed. Two sets of collinear marks were placed at the edges of the substrate. Rotational and translational errors were calculated and compensated using the marks. Processes having different scales were bridged through this alignment method. Various materials were utilized, and accuracy was less than 50 nm when the length of the substrate was less than 13 mm. The alignment method was employed to fabricate a V-shaped structure and step-shaped structure using polymer, ceramic, and metal.

Focused ion beam chemical vapor deposition (FIB-CVD) processes can be used to fabricate nano-/microstructures by enabling highly localized material deposition. Due to these advantages, the FIB-CVD process has been utilized extensively as a method for material analysis and device fabrication in the fields of nano-/microscale electronics, sensors, drivers, bio, and optics. In this study, we fabricated shape memory alloy (SMA) carbon composites using an FIB-CVD process and performed a micro-tensile test to evaluate the mechanical properties of the fabricated composites. According to the results of the tensile test, the fabricated composite structure had higher stiffness values and lower maximum tensile strength values than general SMA materials. Based on our experimental results, we fabricated an SMA microscale bending actuator by localized carbon block deposition and evaluated the bending characteristics of the microactuator.

This paper investigates how people perceive the same material differently according to sex and nationality and what types of materials they prefer. We surveyed the sense of and preference for materials through questionnaires. The survey used five specimens made of zirconia, alumina, aluminum alloy, titanium alloy, and polycarbonate, and was conducted in four cities: Seoul and Ansan (Korea), Atlanta (USA), and Arusha (Tanzania). The survey consisted of three tests (a tactile test, a visual with tactile test, and an acoustic test). Except for the visual with the tactile test, the tests were conducted without any visual information. Using a statistical method, it was found that people feel the same materials differently depending on their sex and nationality. Furthermore, evaluation items which are correlated with material preferences such as roughness, coldness, familiarity, stiffness and color brightness levels were found, with these results showing that the evaluation items related to the preferences differ depending on the person’s sex and nationality.

We develop a numerical simulation describing the dynamic evolutionary deposition associated with the focused ion beam-induced chemical vapor deposition (FIB-CVD) process. It is generally accepted that emitted electrons generated by incident ions trigger the dissociation of precursor molecules adsorbed onto the surface of the substrate or deposit. Therefore, it is essential to detect emitted electrons inside the solid substrate and the deposit, and to calculate the surface positions at which the electrons are emitted. However, this has traditionally been difficult. The Hausdorff distance (HD) is a numerical method enabling rapid calculation of the distance between two objects, and is widely used for pattern-matching and object recognition in image-processing. In our numerical simulation, we use the HD concept to solve the difficulties of determining whether an electron is emitted, and the emission position, during time-dependent deposition. In addition, the modified cellular automata (CA) model was combined with an HD map to simulate deposition over time. We ran a Monte Carlo simulation of the trajectories of ions and electrons. Finally, the simulation results were verified experimentally.

Perfluoroalkoxy alkane (PFA) film-based microelectrode arrays were fabricated in monolithic structure with pretreatment of plasma on the surface followed by patterning gold electrode array without additional adhesion metal layer. The encapsulation of patterned fluoropolymer layer was thermally laminated at the temperature of under its melting point, interleaved between Polytetrafluoroethylene (PTFE) sheets which indicate formation of micro-corrugated pattern. The fabricated device was optically opaque, however, transparent in solution due to the diffraction of light. Packaged substrate was easily processable with focused ion beam laser machine in high resolution. According to excellent reliability, PFA based micro gold electrode can be applied in a variety of biomedical application such as artificial retina, neural sensors with chronic implantation.

Recent legislation and initiatives have precipitated a considerable shift toward sustainable development. Accordingly, studies into green manufacturing and applications have been conducted by numerous researchers. In this review, future perspectives of sustainable manufacturing and applications are evaluated and analyzed based on research databases. More specifically, the current status and historical trajectory of selected research areas are evaluated using data from the Web of Science library and the Journal Citation Reports (JCR). State-of-the-art sustainable manufacturing research is presented, and related journals are discussed according to research area. Selected journals and research subjects are assessed in terms of H-indices and the number of published articles, to evaluate the attention paid to, and importance of, each subject. To further the discussion on future perspectives, the historical trajectories of the research areas are explored. For example, technologies described in a greener machine tool review article were classified according to a technology hierarchy, and their historical changes were evaluated. Selected journals and subjects were matched to categorical hierarchies, and the development stages were assessed based on a four-stage model (early, emerging, developed, and saturated stages). The results showed that sustainable manufacturing and applications have dramatically emerged in the last decade. In this review, insights are provided into the status and future of sustainable technologies through the suggestion of evaluation methods and provision of examples.

Manufacturing paradigms have historically been shaped by social, economic, and technological aspect, including limitations and needs. Design for manufacturing (DFM) has been the main paradigm for last three decades since design is defined by the limitations of available manufacturing processes. Since reducing the time required for the development of new products has been one of the key issues for businesses, removing the gap between designers and manufacturers has been one of today’s main goals. Many methods were developed to reduce this gap including information and communication technologies (ICT). However, current issues have been shifting towards design-related issues such that researchers have been trying to make products desired by the customers rather than that which is cheaper to manufacture. In this article, hybrid manufacturing (HM) and the concept of smart factory are introduced as key technologies for the future paradigm of manufacturing: Manufacturing for Design (MFD). Issues related to the development of HM process and examples of HM process are explained, and the importance of smart factories for the implementation of MFD is shown. Finally, future trends of HM and smart factory are predicted at the end of this article.

A novel nanoscale 3D printing process was developed by integrating nanoparticle printing, micro-machining, and focused ion beam technology. Aerodynamically focused nanoparticle (AFN) printing, a room-temperature direct printing technique using shock-induced aerosol generation, was adopted for material formation, and focused ion beam (FIB) was used for profiling the positioned material. Micro-machining was used to assist and bridge these two processes at different scales, using tools with diameters of 30 μm. Various 2.5D and 3D structures were printed using metal/ceramic nanoparticles with no solvent or post-treatment technique. Some applications are shown in the range from sub-micron to hundreds of micrometers.

In this paper, a total of 57 micro and nano scale hybrid manufacturing processes are reviewed. These processes are categorized in terms of process timing and process type. Process timing is one of the most important aspects of manufacturing, and three different process schemes — concurrent, main/assistive (M/S) separate, and main/main (M/M) separate — are considered. The process type is categorized as either geometrically additive or subtractive, and all hybrid processes are categorized into combinations of additive, subtractive, and assistive process. Features and advantages are described for each of these classifications. Machining is found to be the most common process for both micro and nano-scale hybrid manufacturing. Of micro scale hybrid manufacturing schemes, 74.4% use assistive processes as a secondary process because the main purpose of most micro scale hybrid manufacturing is to improve the quality of the process. In nano scale manufacturing, 61.5% of hybrid manufacturing schemes employ assistive processes, since these processes typically focus on the fabrication of parts that are difficult to fabricate using a single, existing process. Based on a summary of published work, future trends in hybrid manufacturing at the micro and nano scale are suggested.

The purpose of this study is to prescribe the influence of Si in WC-Ni Hard Metal. For the manufacture of WC-Ni Hard Metal according to Si content, the researcher manufactured WC-Ni mixed powder which 0wt.%~1.5wt.% of Si was added to after selecting Ni which a fixed amount of B was added to, and then manufactured sintered body by implementing vacuum-sintering to the mixed powder. This study implemented the analysis with HRA, TRS, XRD, SEM, and EPMA to observe densification, alloying reaction, and mechanical properties of the sintered body. In WC-Ni Hard Metal, shrinkage showed a tendency to increase as Si content increased. It is considered that the densification was promoted during liquid phase sintering, because a melting point of binder metal got lower as Si content increased. The hardness of WC-Ni Hard Metal was kept uniformly up to 0.6wt.%Si, and then it showed the tendency to increase from the level of 0.9wt.%Si. It is considered that the hardness of B and Si added to Ni binder metal formed BNi3 phase and Ni3Si phase which had high hardness, and these compound phases restrained the growth of WC particle. It is considered that transverse rupture strength of WC-Ni Hard Metal according to the increase of Si content was increased by the decrease of mean free path of WC particle caused by the improvement of fluidity according to the restrained growth of WC particle by of BNi3 phase and Ni3Si phase, and caused by the improved fluidity according to the decreased melting point of Ni binder metal.

A hybrid 3D printing process was developed for multiple-material/freeform nano-scale manufacturing. The process consisted of aerodynamically focused nanoparticle (AFN) printing, micro-machining, focused ion beam milling, and spin-coating. Theoretical and experimental investigations were carried out to improve the compatibility of each of the processes, enabling bridging of various different techniques. The resulting hybrid process could address the limitations of individual processes, enabling improved process scaling and dimensional degrees of freedom, without losing the advantages of the existing processes. The minimum structure width can be reduced to 50 nm using undercut structures. In addition, AFN printing employs particle impact for adhesion, and various inorganic materials are suitable for printing, including metals and functional ceramics. Using the developed system, we fabricated bi-material cantilevers for applications as a thermal actuator. The mechanical and thermal properties of the structure were investigated using an in situ measurement system, and irregular thermal phenomena due to the fabrication process were analyzed. We expect that this work will lead to improvements in the area of customized nano-scale manufacturing, as well as further improvements in manufacturing technology by combining different fabrication techniques.

Nano particle deposition system (NPDS) had been developed for the creation of micro/nano structures with multimaterials in order to develop the micro/nano devices on the basis of specific localized surface on the multilayer. However, micro structures fabricated by NPDS show different mechanical properties when it compared to bulk material because of its porous and uneven deposition structure. To achieve reasonable mechanical properties of the structure fabricated by nanoscale 3D printing system, it requires in-situ mechanical property test method. Herein, a new approach for in-situ nanomechanical characterization system using microforce sensor and nanomanipulator installed in focused ion beam system. In this research, experimental setup for mechanical characterization was developed and mechanical property test was done in Focused Ion Beam (FIB) system. The specimen was fabricated by FIB milling process, then manipulation and compression processes are operated by this characterization system with real time imaging. The test was done for silver microstructures fabricated by NPDS and results show weaker hardness and smaller young’s modulus than bulk material.Copyright © 2014 by ASME