bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation of the Functional Properties of Additively-Fabricated Triply Periodic Minimal Surface-Based Bone Scaffolds for the Treatment of Osseous Fractures
Authors: Chaffins Abigail , Yu Mohan , Claudio Pier Paolo , Day James B. , Salary Roozbeh (Ross) 
Published: August 2021

Abstract
Fused deposition modeling (FDM), is a direct-write material extrusion additive manufacturing process, which has emerged as a method of choice for the fabrication of a wide range of biological tissues and structures. FDM allows for non-contact, multi-material deposition of a broad spectrum of functional materials for tissue engineering applications. However, the FDM process is intrinsically complex, consisting of a multitude of parameters as well as material-machine interactions, which may adversely influence the mechanical properties, the surface morphology, and ultimately the functional integrity of fabricated bone scaffolds. Hence, process optimization in addition to physics-based characterization of the FDM process would be inevitably a need.
The overarching goal of this research work is to fabricate biocompatible, porous bone scaffolds, incorporating autologous human bone marrow mesenchymal stem cells (hBMSCs), for the treatment of osseous fractures, defects, and eventually diseases. The objective of this work is to investigate the mechanical properties of several triply periodic minimal surface (TPMS) bone scaffolds, fabricated using fused deposition modeling (FDM) additive manufacturing process.
In this study, biocompatible TPMS bone scaffolds were FDM-deposited, based on a medical-grade polymer composite, composed of polyamide, polyolefin, and cellulose fibers (named PAPC-II). In addition, the experimental characterization of the TPMS bone scaffolds was on the basis of a single factor experiment. The compression properties of the fabricated bone scaffolds were measured using a compression testing machine. Furthermore, a digital image processing program was developed in the MATLAB environment to characterize the morphological properties of the fabricated bone scaffolds.
A Semi-Supervised Multiclass Anomaly Detection Approach for Partially Labeled In-Process Measurement Data
Authors: Cohen Joseph , Ni Jun 
Published: August 2021

Abstract
Machine learning and other data-driven methods have developed at a prolific rate for industrial applications due to the advent of industrial big data. However, industrial datasets may not be especially well-suited to supervised learning approaches that require extensive domain knowledge in the complete and accurate labeling of datasets. To address these challenges, a semi-supervised learning approach is proposed that makes use of partially labeled subsets. The proposed methodology is applied to high-dimensional in-process measurement data, utilizing a convolutional autoencoder for unsupervised feature extraction. A multiclass extension for semi-supervised anomaly diagnosis is proposed that utilizes principal component analysis as the basis for anomaly scoring, and the proposed approach intersects the results of targeted one-against-all phases on partially labeled sets to classify faults. Experiments in a case study on semiconductor manufacturing measurement data are performed to explore the relationship between latent features extracted and anomaly detection performance. The application of the proposed algorithm achieves a true positive detection rate of over 90% with false positive rate under 9% for both local and global anomaly types, with these results accomplished while reducing over 99% of the original input data dimensions. In addition, the approach also allows for positive samples to be identified that were previously undetected by human experts. These results are promising for the application of the proposed semi-supervised methodology in real industrial settings.
Predictions of Cutting Force and Tool Wear in Gear Power Skiving
Authors: Ren Zongwei , Fang Zhenglong , Arakane Takuhiro , Kizaki Toru , Feng Yannan , Nishikawa Tsukasa , Kugo Junshi , Nabata Eiji , Sugita Naohiko 
Published: August 2021

Abstract
Power skiving is a promising method that can enhance the efficiency of gear machining. The machining mechanism is complicated due to several factors, such as the continuous variation in the rake angle and undeformed chip thickness. The tool wear process is also difficult to be evaluated due to the constantly varying in cutting conditions. Hence, to make a comprehensive understanding of the cutting process, we proposed a parametric modeling process based on the kinematics of power skiving. In this model, the undeformed cutting chip was calculated in each pass and shows the consistency with deformed cutting chip in experiments. The effective rake angle and undeformed cutting chip thickness were defined, calculated, and displayed on undeformed cutting chip for a better understanding of the cutting process. The cutting force and tool crater wear were calculated by estimating the distribution of the stress and temperature on the rake face of the cutting tool. Multiple radial-feed experimental evaluations were conducted with the gears of construction vehicles. In the results, the predicted margin of the absolute error of the normal force on the rake face was under 5% in every pass. The wear distribution on the rake face is consistent with the superimposed tool-chip contact area. The results show high potential for the optimization of the cutting tool or cutting conditions in gear power skiving.
Framework for User-Friendly Modeling of Energy Use in Fused Deposition Modeling
Authors: Wang Xiange , Kent Philip , Linke Barbara S. 
Published: August 2021

Abstract
Additive manufacturing has experienced rapid growth in recent years due to its advantage of producing less waste and prototyping at a faster rate compared to traditional manufacturing. As the demand for customized and rapidly manufactured parts continues to expand, in particular Fused Deposition Modeling (FDM) as an easily accessible process has been growing significantly. A lot of research in this area focuses on improving the print part surface roughness and dimensional accuracy, but there is a lack of in-depth analysis on the environmental impact and energy consumption of FDM machines as well as on user-friendly energy models. This paper offers a review of selected efforts on modeling energy consumption through physics-based methods as well as on empirical methods and proposes a framework structure for energy modeling targeted towards user-friendliness and transparency. The user should be able to improve FDM efficiency in the form of energy and/or time efficiency, gain understanding of printer energy consumption and obtain recommendations for printer setting and usage. A Graphic User Interface of the model and a model design structure are proposed in this work along with useful analytical equations and methods. Modeling of waste heat and inclusion of part quality are further features of the suggested energy model framework.
A Study of the Efficacy of Flame Electrical Resistance for Standoff Measurements During the Oxyfuel Cutting Process
Authors: Martin Christopher R. , Untaroiu Alexandrina , Xu Kemu , Rahman S. M. Mahbobur 
Published: August 2021

Abstract
This is a study of the suitability of preheat flame electrical resistance as a potential method for measuring the standoff distance an oxyfuel cutting torch and a work piece. Careful scrutiny of forty seven (47) individual experiments demonstrate that when cut quality is good, there is a linear repeatable relationship between the two with uncertainty about ± .3mm (.015in). As the cut quality degrades, the formation of top-edge dross reduces the electrical path length in the flame, and momentary reduction in the reaction rate in the kerf reduces the free electrons in the flame, causing rises in flame resistance. In these conditions, measurement uncertainty reduces to ± 1mm (.040in) or worse.
Impacts of Process Parameters on Shape Memory Properties of Stereolithography Manufactured Parts: An Experimental Analysis
Authors: Zhao Jing , Han Muyue , Li Lin 
Published: August 2021

Abstract
The emergence of smart materials coupled with additive manufacturing technology has provided competitive advantages over traditional manufacturing systems in terms of manufacturing flexibility, product functionality, and the ability to switch between multiple phases under given external stimuli. Although the fabricability of shape memory materials has been widely explored in stereolithography systems, the shape memory performance of printed smart structures has not been extensively studied. More specifically, in current literature, the printing process is mainly considered independent of material characteristics, and a lack of information is reported on how the printing parameters affect the shape fixity and free recovery performance of the printed parts. Therefore, this work is dedicated to experimentally investigating the influences of parameters from both the stereolithography printing process and thermomechanical process (i.e., shape programming and free recovery) on the shape memory properties. Five parameters, including layer thickness, scan speed, maximum programmed angle, hold time, and recovery time, are experimentally analyzed for their impacts on the shape morphing capabilities. According to the results of this study, a variation of 14.33% on the free recovery ratio can be observed when the scan speed is altered. In addition, the printing process parameters exhibit high levels of dominance in affecting the shape memory performance over parameters involved in the thermomechanical process, such as hold time and maximum programmed angle.
Precision Evaluation of NeXus, a Custom Multi-Robot System for Microsystem Integration
Authors: Wei Danming , Tofangchi Alireza , Sherehiy Andriy , Saadatzi Mohammad Hossein , Alqatamin Moath , Hsu Keng , Popa Dan O. 
Published: August 2021

Abstract
Industrial robots, as mature and high-efficient equipment, have been applied to various fields, such as vehicle manufacturing, product packaging, painting, welding, and medical surgery. Most industrial robots are only operating in their own workspace, in other words, they are floor-mounted at the fixed locations. Just some industrial robots are wall-mounted on one linear rail based on the applications. Sometimes, industrial robots are ceiling-mounted on an X-Y gantry to perform upside-down manipulation tasks. The main objective of this paper is to describe the NeXus, a custom robotic system that has been designed for precision microsystem integration tasks with such a gantry. The system tasks include assembly, bonding, and 3D printing of sensor arrays, solar cells, and microrobotic prototypes. The NeXus consists of a custom designed frame, providing structural rigidity, a large overhead X-Y gantry carrying a 6 degrees of freedom industrial robot, and several other precision positioners and processes. We focus here on the design and precision evaluation of the overhead ceiling-mounted industrial robot of NeXus and its supporting frame. We first simulated the behavior of the frame using Finite Element Analysis (FEA), then experimentally evaluated the pose repeatability of the robot end-effector using three different types of sensors. Results verify that the performance objectives of the design are achieved.
Anisotropic Cutting Force Characteristics in Milling of Maraging Steel Processed Through Selective Laser Melting
Authors: Tamura Shoichi , Matsumura Takashi , Ezura Atsushi , Mori Kazuo 
Published: August 2021

Abstract
Additive manufacturing process of maraging steel has been studied for high value parts in aerospace and automotive industries. The hybrid additive / subtractive manufacturing is effective to achieve tight tolerances and surface finishes. The additive process induces anisotropic mechanical properties of maraging steel, which depends on the laser scanning direction. Because anisotropy in the workpiece material has an influence on the cutting process, the surface finish and the dimension accuracy change according to the direction of the cutter feed with respect to the laser scanning direction. Therefore, the cutting parameters should be determined to control the cutting force considering material anisotropy. The paper discusses the cutting force in milling of maraging steel stacked with selective laser melting, as an additive manufacturing process. Anisotropic effect on the cutting forces is proved with the changing rate of the cutting force in milling of the workpieces stacked by repeating laser scanning at 0/90 degrees and 45/−45 degrees. The cutting forces, then, are analyzed in the chip flow models with piling up of orthogonal cuttings. The force model associates anisotropy with the shear stress on the shear plane. The changes in the cutting forces with the feed direction are discussed in the cutting tests and analysis.
Hybrid-Light-Source Stereolithography for Fabricating Macro-Objects With Micro-Textures
Authors: Jia Wenxuan , Leung Yuen-Shan , Mao Huachao , Xu Han , Zhou Chi , Chen Yong 
Published: August 2021

Abstract
Microscale surface structures are commonly found on macroscale bodies of natural creatures for their unique functions. However, it is difficult to fabricate such multi-scale geometry with conventional stereolithography processes that rely on either laser or digital micromirror device (DMD). More specifically, the DMD-based mask projection method displays the image of a cross-section of the part on the resin to fabricate the entire layer efficiently; however, its display resolution is limited by the building area. In comparison, the laser-based vector scanning method builds smooth features using a focused laser beam with desired beam-width resolution; however, it has less throughput for its sequential nature. In this paper, we studied the hybrid-light-source stereolithography process that integrates both optical light sources to facilitate the fabrication of macro-objects with microscale surface structures (called micro-textures in the paper). The hardware system uses a novel calibration approach that ensures pixel-level dimensional accuracy across the two light sources. The software system enables designing the distribution and density of specific microscale textures on a macro-object by generating projection images and laser toolpaths for the two integrated light sources. Several test cases were fabricated to demonstrate the capability of the developed process. A large fabrication area (76.8 mm × 80.0 mm) with 50 μm micro-features can be achieved with a high throughput.
Design and Manufacturing of Topology Optimized Heat Sinks Made of Copper Using 3D Printing
Authors: Taha Bilal , Patil Sandeep , Dennis Brian H. 
Published: August 2021

Abstract
The performance of a heat sink is highly dependent on the overall surface area available for convective heat transfer. Topology optimization technique has widely been used to achieve complex thermal designs which are more compact in size and have larger surface areas. In addition to it, the optimized heat sink designs are much lighter and have reduced mass compared to conventional designs. Conventionally thermal topology optimization is performed using numerical analysis which considers both conduction and convection process coupled together. The authors in this paper have presented a simple and a novel methodology for performing thermal topology optimization of heats sinks using ANSYS workbench software. To manufacture the complex design of the heat sink, Fused Filament Fabrication technique commonly known as 3D printing process was used. Virtual Foundry’s Copper-PLA filament having 90% copper and 10% PLA material was used as the primary material of choice. Furthermore, to achieve a heat sink made purely of copper, sintering process of the 3D-printed part was carried out in a vacuum furnace. The optimized design proved to be more thermally efficient and compact in size whereas the manufacturing technique used demonstrated quite an economical way of producing such complex topology optimized designs for heat sinks.
Vibration-Assisted Insertion of Flexible Neural Microelectrodes With Bio-Dissolvable Guides for Medical Implantation
Authors: Wang Yi , Shih Yen Yu Ian , Lee Yuan-shin 
Published: August 2021

Abstract
This paper presents vibration-assisted insertion of flexible neural electrodes with bio-dissolvable guides to deliver accurate microprobe insertion with minimized tissue damage. Invasive flexible neural microprobe is an important new tool for neuromodulation and recording research for medical neurology treatment applications. Flexible neural electrode probes are susceptible to bending and buckling during surgical implantation due to the thin and flexible soft substrates. Inspired by insects in nature, a vibration-assisted insertion technique is developed for flexible neural electrode insertion to deliver accurate microprobe insertion with minimized tissue damage. A three-dimensional combined longitudinal-twisting (L&T) vibration is used to reduce the insertion friction force, and thus reducing soft tissue damage. To reduce the flexible microelectrode buckling during surgical insertion, a bio-dissolvable Polyethylene glycol (PEG) guide is developed for the enhancement of flexible neural probe stiffness. Combining these two methods, the insertion performance of the flexible neural probe is significantly improved. Both the in vitro and the in vivo experiments were conducted to validate the proposed techniques.
Integrating Friction-Stir Back Extrusion to Powder Metallurgy
Authors: Dhoka Sahil , Wagner Scott W. , Abhi Himansshu , Hendrickson Nicholas V. , Emblom William J. 
Published: August 2021

Abstract
Reducing fuel consumption has been a driving factor for researchers and manufacturers to continually develop improved methods for reducing the weight of automobiles or lightweighting. These vehicle lightweighting demands have directed researchers to look to using materials that are typically more difficult to manufacture in their studies. As a result, friction stir processing techniques are being looked at more closely. There are advantages to using friction stir methods. Dissimilar metals can be welded and fine-grained products can be created using friction stir methods to name a few. It can be an ideal solution for manufacturing high-conductive metals and alloys. Foamed aluminum tube similar to the one shown by Yoshiko Hangai et al [1] can be formed using the proposed process which could be used to develop lightweight automobile components.
This paper provides preliminary results and insights gained when fine metal powders were used in a friction stir back extrusion (FSBE) setup. The tooling consisted of a D2 tool steel die with an H13 rotating probe mounted in a CNC mill. Within the die, commercially pure aluminum powder was topped by an aluminum cap with a milled pocket in the center. This pocket was used to locate the spin tool in the center of the cap and reduce the potential for the tool to drift and deflect. The cap was also used for compacting the powdered aluminum. X-ray diffraction indicated that Al13Fe4 was formed, indicating that the temperature within the die reached a minimum of 800°C and also indicated that the powder had the potential to partially sinter and melt.
Characterization of Co-Cr-Mo Alloys Manufacturing via Directed Energy Deposition
Authors: Liu Michael , Kuttolamadom Mathew 
Published: August 2021

Abstract
In this study, Co-Cr-Mo samples that were fabricated via directed energy deposition (DED) at various laser powers and powder feed rates were characterized to ascertain their microstructure and mechanical properties. Co-Cr-Mo is a common alloy for total hip and knee replacements, dental, and support structures due to its biocompatibility, hardness and abrasion resistance, making them a preferred alloy for metal-on-metal (MOM) contact. This study was undertaken to understand the pertinent process parameters that would generate structurally viable bulk structures. High-resolution microscopy and spectroscopy revealed the presence of networked and jagged carbides with varying amounts of Mo. Further, XRD confirmed the presence of the γ and ε phases. Micro- and nano-scale characterization of the alloy fabricated at different process conditions showed material properties in line with those made via traditional processing approaches such as casting. Altogether, this investigation provided an understanding of the effect of additive manufacturing process parameters on the microstructure and properties of Co-Cr-Mo.
Effects of Size Reduction on the Failure Mechanism of 3D Printed PLA+ Parts
Authors: Decker Zane , Makulinski Mason , Vispute Suprita , Sundaram Murali 
Published: August 2021

Abstract
Fused Deposition Modeling (FDM) with Poly(lactic Acid) plus (PLA+) is frequently used in rapid prototyping and 3D printing of complex shapes. Owing to their light weight, manufacturability and cost effectiveness, thermoplastic parts made by FDM are increasingly used in several applications ranging from tissue engineering to consumer goods industry. Understanding the size effects on the strength of these parts is essential to extend their use in the microsystem applications. This paper studies the effect of scale on the mechanical properties and failure mechanisms of a 3D printed parts made by FDM. Process parameter such as extrusion temperature, infill density, infill pattern, print speed, layer thickness and nozzle diameter were kept consistent for this experiment. Five samples each with a square cross-sectional area of side lengths of 2mm, 4mm, 6mm, and 10mm were subjected to a tensile test. It was observed that parts with a smaller cross-sectional area experienced ductile failure as opposed to brittle fracture in larger cross-sectional area. Failure is shown to occur at sections where the geometry changes for brittle fractures while it occurs at the center of the parts displaying ductile failure. Results of the tensile test show a non-uniform ultimate yield strength across the four sizes. Crystallization of the material due to nozzle temperature at extrusion could be a contributing factor to failure discrepancies. Increase in the cycle time is theorized to improve the layer to layer adhesion of the part thereby affecting its mode of failure.
Investigation of the Dynamic Response of a Multispot System at Joining Using Ultrasonic Welding
Authors: Lee Tae Hwa , Wang Pei-Chung , Hu S. Jack , Banu Mihaela 
Published: August 2021

Abstract
Ultrasonic welding is one of the most practical joining method for polymer composite materials and has been adapted in the aerospace and automotive industries. To effectively join polymer composite assemblies, it is critical to understand the dynamic response of the welding system so that sound heating generation and welding sequences in the ultrasonic welding of the assemblies can be properly obtained. This study presents a dynamic response model of a multi-spot configuration assembly using ultrasonic welding. Here, a dynamic model of joining a U-shaped carbon fiber reinforced thermoplastic composite part with a flat part is developed and analyzed through the ratio between the frequencies generated at different locations of the spot with respect to the edges of the assembly and the natural frequency. Finally, this ratio is correlated with the weld quality of the multiple spot configuration. Guidelines for designing multisport sequence are extracted. This study provides a method to design the welding sequence in ultrasonic welding of carbon fiber reinforced composites.