bluuebunny/crossref_metadata_2025_split huggingface dataset:
Surface Roughness Measurement of Additive Manufactured Parts Using Focus Variation Microscopy and Structured Light System
Authors: Zhang Xiao , Suresh Vignesh , Zheng Yi , Wang Shaodong , Li Qing , Lyu Hao , Li Beiwen , Qin Hantang 
Published: November 2019

Abstract
Surface roughness is a significant parameter when evaluating the quality of products in the additive manufacturing (AM) industry. AM parts are fabricated layer by layer, which is quite different from traditional formative or subtractive methods. A uniform feature can be obtained along the direction of the AM printhead movement on the surface of manufactured components, and a large waviness value can be found in the direction perpendicular to printhead movement. This unique characteristic differentiates additive manufactured parts from casted or machined parts in the way of measuring and defining surface roughness. Therefore, it is necessary to set up new standards to measure surface roughness of AM parts and analyze the variation in the topographical profile. The most widely used instruments for measuring surface roughness are profilometer and laser scanner, but they cannot generate 3D topographical surfaces in real-time. In this work, two non-contact optical methods based on Focus Variation Microscopy (FVM) and Structured Light System (SLS) were adopted to measure the surface topography of the target components. The FVM captures images of objects at different focus levels. By translating the object’s position based on focus profile, a 3D image is obtained by data fusion. The lab-made microscopic SLS was used to perform simultaneous whole surface scanning with the potential to achieve real-time 3D surface reconstruction. The two optical metrology systems generated two totally different point cloud data sets. Limited research has been conducted to verify whether the point cloud data sets generated from different optical systems are following the same distribution. In this paper, a statistical method was applied to test the difference between two systems. By using data analytics approaches for comparison analysis, it was found that surface roughness based on the FVM and the SLS systems has no significant difference from a data fusion point of view, though point cloud data generated were completely different in values. In addition, this paper provided a standard measurement approach for a real-time, non-contact method to estimate the surface roughness of AM parts. The two metrology techniques can be applied for in-situ real-time surface analysis and process planning for AM.
Localized Microstructures Fabrication Through Standing Surface Acoustic Wave and User-Defined Waveguides
Authors: Wang Yancheng , Han Chenyang , Mei Deqing , Xu Chengyao 
Published: November 2019

Abstract
Polymer-based substrates with patterned microstructure on the surfaces, e.g., cell culturing scaffolds, have been utilized in biomedical applications. This paper develops a novel method to fabricate the localized microstructure on the polymer-based substrate with the assistance of standing surface acoustic wave (SAW) and user-defined acoustic waveguides. The specific designed acoustic waveguides can localize the standing acoustic waves and transmit to the liquid film and excite patterned microstructures on the surface, then using ultraviolet (UV) to solidify the substrate with patterned microstructures. The structural design and fabrication of the SAW device and three different shaped acoustic waveguides are presented. Then, experimental setup and procedures to verify the polymer-substrate with localized microstructures fabrication are performed. By using the different shape of the acoustic waveguides, several types of patterned microstructures with different morphologies are successfully fabricated. Results demonstrated that the proposed fabrication method is an effective way to fabricate polymer-based substrate with localized patterned microstructures, which may have potential in the research on tissue engineering, cell-cell interaction, and other biomedical applications.
A Review on Additive Manufacturing of Ceramics
Authors: Mansfield Brooke , Torres Sabrina , Yu Tianyu , Wu Dazhong 
Published: November 2019

Abstract
Additive manufacturing (AM), also known as 3D printing, has been used for rapid prototyping due to its ability to produce parts with complex geometries from computer-aided design files. Currently, polymers and metals are the most commonly used materials for AM. However, ceramic materials have unique mechanical properties such as strength, corrosion resistance, and temperature resistance. This paper provides a review of recent AM techniques for ceramics such as extrusion-based AM, the mechanical properties of additively manufactured ceramics, and the applications of ceramics in various industries, including aerospace, automotive, energy, electronics, and medical. A detailed overview of binder-jetting, laser-assisted processes, laminated object manufacturing (LOM), and material extrusion-based 3D printing is presented. Finally, the challenges and opportunities in AM of ceramics are identified.
Numerical Study of Porosity Formation With Implementation of Laser Multiple Reflection in Selective Laser Melting
Authors: Cheng Bo , Tuffile Charles 
Published: November 2019

Abstract
In selective laser melting (SLM) process, the build part quality is determined by process parameters such as laser scanning speed and power. The presence of porosity, a major printing defect that significantly affects part performance, may arise in laser melting process due to insufficient or excess energy input. The improvement of build quality heavily depends on fundamental understanding of porosity formation in the SLM process. In this study, the discrete element method (DEM) has been utilized to simulate the creation of a newly deposited powder layer. A computational fluid dynamics (CFD) model was developed to simulate the melting and solidification process of Ti-6Al-4V powders in the SLM process. The thermo-fluid model includes effect of surface tension and recoil pressure as well as laser ray multi-reflection in keyhole. The predictability of the developed CFD model has been validated against literature experimental data. It is found that the collapse of an unstable deep keyhole was responsible for the formation of pores. In addition, higher laser scanning speeds tend to form unstable melt pools, e.g., melt pool break-up.
Effect of Post Laser Shock Peening on Microstructure and Mechanical Properties of Inconel 718 by Selective Laser Melting
Authors: Sidhu Kuldeep Singh , Wang Yachao , Shi Jing , Vasudevan Vijay K. , Mannava Seetha Ramaiah 
Published: November 2019

Abstract
This study investigates the effects of laser shock peening (LSP) on residual stress, near surface modification, and hardness of Inconel 718 (IN718) specimens manufactured by selective laser melting (SLM) technique. Optical microscope and electron backscattered diffraction (EBSD) is used to characterize the microstructures of both heat-treated and as-built specimens. A nanoindentation test is performed to determine the properties such as the hardness of as-built and heat-treated specimens. Afterward, the hardness along the distance from the LSP treated surface is also defined. To investigate the effect of LSP energy on the mechanical properties of specimens, two levels of LSP energy, e.g., low energy LSP (6.37 GW/cm2) and high energy LSP (8.60 GW/cm2), are carried out on selected samples. With the increase in laser energy density, it is found that both compressive residual stress and hardness increase after LSP treatment. The as-built specimens after high energy LSP treatment show the compressive residual stress of −875 MPa, and the surface hardness increases from 468 HV to 853 HV.
Modeling and Experimental Validation of Part-Level Thermal Profile in Fused Filament Fabrication
Authors: Roy Mriganka , Yavari Reza , Zhou Chi , Wodo Olga , Rao Prahalad 
Published: November 2019

Abstract
Part design and process parameters directly influence the spatiotemporal distribution of temperature and associated heat transfer in parts made using additive manufacturing (AM) processes. The temporal evolution of temperature in AM parts is termed herein as thermal profile or thermal history. The thermal profile of the part, in turn, governs the formation of defects, such as porosity and shape distortion. Accordingly, the goal of this work is to understand the effect of the process parameters and the geometry on the thermal profile in AM parts. As a step towards this goal, the objectives of this work are two-fold: (1) to develop and apply a finite element-based framework that captures the transient thermal phenomena in the fused filament fabrication (FFF) additive manufacturing of acrylonitrile butadiene styrene (ABS) parts, and (2) validate the model-derived thermal profiles with experimental in-process measurements of the temperature trends obtained under different feed rate settings (viz., the translation velocity, also called scan speed or deposition speed, of the extruder on the FFF machine). In the specific context of FFF, this foray is the critical first-step towards understanding how and why the thermal profile directly affects the degree of bonding between adjacent roads (linear track of deposited material), which in turn determines the strength of the part, as well as, propensity to form defects, such as delamination. From the experimental validation perspective, we instrumented a Hyrel Hydra FFF machine with three non-contact infrared temperature sensors (thermocouples) located near the nozzle (extruder) of the machine. These sensors measure the surface temperature of a road as it is deposited. Test parts are printed under three different settings of feed rate, and subsequently, the temperature profiles acquired from the infrared thermocouples are juxtaposed against the model-derived temperature profiles. Comparison of the experimental and model-derived thermal profiles confirms a high-degree of correlation therein, with maximum absolute error less than 10%. This work thus presents one of the first efforts in validation of thermal profiles in FFF via in-process sensing. In our future work, we will focus on predicting defects, such as delamination and inter-road porosity based on the thermal profile.
Micro-Scale Fiber Cutting Geometry Predictions During Milling of Carbon Fiber Reinforced Polymers (CFRP) Composites
Authors: Fu Xingyu , Song Kyeongeun , Kim Dongmin , Kim Gyuho , Min Byung-Kwon , Jun Martin Byung-Guk 
Published: November 2019

Abstract
Carbon Fiber Reinforced Polymer (CFRP) is a light-weight material with high strength and highly corrosion resistance, and hence is widely applied in aerospace industries. However, milling of CFRP usually generates machining defects (for instance, delamination and pull-out fibres), making processed surface unqualified to meet the requirement of aerospace application. Therefore, prediction for machining quality should be conducted before milling processing to avoid potential loss in massive production. Fracture behaviours of micro-scale fibres and matrix have a significant influence on the final machined surface, and such material removal mechanism can be mainly determined by micro-scale geometrical relationships between carbon fibers and milling teeth. In this paper, a micro-scale geometrical calculation software for CFRP milling is provided based on Dexel model. The software can generate geometrical parameters, for example, cutting angle, cutting length and engagement angle, for the whole milling process. Milling defects and milling forces can be conducted based on those micro-scale geometrical parameters.
Preliminary Study on Fractal-Based Monopole Antenna Fabricated Using 3D Polymer Printing and Selective Electrodeposition Process
Authors: James Sagil , Birar Shubham , Parekh Riken , Jain Kushal , George Kiran 
Published: November 2019

Abstract
Modern wireless communication industries need high performance antennas having better connectivity, ultra-wide bandwidth, lightweight and miniaturized. The current design and manufacturing process for antennas have several limitations. This study aims to address some of the limitations of designing and fabricating modern radio frequency wireless antennas. The study proposes a combination of fractal-based monopole antenna design followed by fabrication using additive manufacturing and selective electrochemical deposition process. Multiple designs of monopole antennas are compared, and the performance testing showed that the three-dimensional fractal-based antenna design showed the highest performance. The results of this study would be extremely crucial for overcoming challenges of modern antenna technologies.
Developing Measurement Science to Verify and Validate the Identification of Robot Workcell Degradation
Authors: Weiss Brian A. 
Published: November 2019

Abstract
Robot systems have become more prevalent in manufacturing operations as the technology has become more accessible to a wider range of manufacturers, especially small to medium-sized organizations. Although these robot technologies have become more affordable, easier to integrate, and greater in functional capability, these advanced systems increase workcell complexity leading to the presence of more fault and failure modes. Given increasing manufacturing competitiveness, maximizing asset availability and maintaining desired quality and productivity targets have become essential. The National Institute of Standards and Technology (NIST) is developing measurement science (e.g., test methods, performance metrics, reference data sets) to monitor the degradation within a manufacturing workcell that includes a six-degree-of-freedom robot arm. Numerous components of the workcell influence the accuracy of the robot’s tool center position. Identifying the component(s) responsible for process degradation prior to the process performing out of specification will provide manufacturers with advanced intelligence to maintain or maximize their performance targets and asset availability. NIST’s research in robot workcell health promotes workcell component health characterization and develops methods and tools to verify and validate this approach. This paper presents the overall research plan and the efforts to date in developing appropriate test methods, identifying key sources of workcell degradation, and presenting baseline performance data that is leveraged for health assessment.
Waste Reduction: A Review of Common Options and Alternatives
Authors: Williams Jewel , Warrington Shelby , Layton Astrid 
Published: November 2019

Abstract
Circular economy aims to address limited resources through the continuous circulation of materials and energy. Recirculating low quality materials for reuse is a sustainability goal that is analogous to the primary function of Nature’s detritus species, a keystone for the proper functioning of ecosystems. Prior applications of ecosystem structure to human network design uncovered that even the most economically successful networks of industries demonstrate a lack of analogous detritus actors in the form of reuse and recycling. The recycling industry’s volatile nature, dependency on international factors, and financial difficulties prevent this strategy from becoming an efficient alternative. Creativity in design, inspired by ecosystems, is proposed here as a method to repurpose manufacturing byproducts that are otherwise seen as low quality waste materials. Realizing the reuse potential of these materials can create detrital-type feedback loops, an attribute that supports the characteristic resilience and efficiency of ecosystems. The work here analyzes existing methods of pursuing circular economy and investigates the potential benefits generated by purposefully adding connects that create detrital-feedback-loops at the consumer and producer levels.
Mechanical Recycling of Low-Density Polyethylene/Carbon Nanotube Composites and its Effect on Material Properties
Authors: Stan Felicia , Stanciu Nicoleta-Violeta , Fetecau Catalin , Sandu Ionut-Laurentiu 
Published: November 2019

Abstract
In this paper, the impact of recycling and remanufacturing on the behavior of low-density polyethylene/multi-walled carbon nanotube (LDPE/MWCNT) composites is investigated. LDPE/MWCNT composites with 0.1–5 wt.%, previously manufactured by injection molding, were mechanically recycled and remanufactured by injection molding and 3D filament extrusion, and the rheological, electrical, and mechanical properties were analyzed and compared with those of virgin composites under the same conditions. Experimental results demonstrate that the recycled LDPE/MWCNT composites have similar rheological, electrical, and mechanical properties to virgin composites, if not better. Therefore, the recycled LDPE/MWCNT composites have a great potential for being used in engineering applications, while reducing the environmental impact.
Failure Detection and Remaining Life Estimation for Ion Mill Etching Process Through Deep-Learning Based Multimodal Data Fusion
Authors: He Anqi , Jin Xiaoning 
Published: November 2019

Abstract
Ion Mill Etching (IME) is an advanced process technology that uses ion-beam sources to remove materials by atomic sandblasting in order to reveal a specific pattern on the substrate. The high-precision capability requires stringent process monitoring and control of the flowcool system which is critical to prevent thermal deformation for temperature sensitive materials from the heat generated from the ion beam irradiation. This study focuses on a multi-sensor data analytics to monitoring the IME process condition — enabling diagnostics and prediction of three main failure mechanisms of the IME flowcool system. A generalizable framework of engineering-based data-driven failure diagnostics and prediction is developed using random forest-based classification and a Deep Long Short-Term Memory (LSTM)-based failure prediction. The proposed framework and methods are demonstrated and validated in an ion mill etching process using multi-sensor data collected from multiple run-to-failure cycles. Three different failure modes related to the flowcool system are detected, identified in real time and the time to the next failure is accurately predicted. The proposed method provides a systematic and generalizable approach for process monitoring and early prediction of failures by using heterogeneous sensor measurements and operational data when under various operating conditions and settings.
Ultrasonic Welding of Soft Polymer and Metal: A Preliminary Study
Authors: Meng Yuquan , Peng Dingyu , Nazir Qasim , Kuntumalla Gowtham , Rajagopal Manjunath C. , Chang Ho Chan , Zhao Hanyang , Sundar Sreenath , Ferreira Placid M. , Sinha Sanjiv , Miljkovic Nenad , Salapaka Srinivasa M. , Shao Chenhui 
Published: November 2019

Abstract
Joining soft polymers and metals is receiving increasing attention in both industry and academia to enable the manufacturing of innovative products. One motivation arises from the production of next-generation heat exchanges, the structure of which is primarily composed of polymers and metals. Waste heat coming from low temperature exhaust gas stream is significant in industries in the U.S. However, traditional heat exchangers that are available to recover heat in the presence of small temperature difference are large and costly, restricting the wide application of such heat exchangers. To address this challenge, a hybrid materials design is proposed to achieve a balance between thermal conductivity and mechanical strength. High quality requirement induced by the changing operating conditions necessitates a strong bonding between polymers and copper. In this research, the possibility of using ultrasonic welding, which is conventionally employed to join dissimilar or similar metal layers, is explored. Preliminary results from welding experiments and tensile shear tests reveal that two bonding modes exist in the welding of PET and copper. Furthermore, analysis of power signals collected during welding shows that one can potentially monitor and optimize welding processes using monitoring signals. It is concluded from this study that ultrasonic welding has excellent potential in joining soft polymers and metals. Future work is also discussed on the process improvement and mechanism investigation.
Fabrication of Copper Foam Plate Using Friction Sintering
Authors: Sharma Vyas Mani , Racherla Vikranth , Pal Surjya Kanta 
Published: November 2019

Abstract
A novel friction sintering process is used to obtain large copper foam plates using sintering and dissolution process. The process ensures easy and quick removal of the sintered product. Heat and pressure generated by downfeed of rotating tungsten tool pressed against a “top plate” results in solid-state sintering of copper powder particles. The large sized sintered part was obtained by providing a scan path for tool covering the “die” containing Cu-NaCl mixture. Note that no pre-compression of Cu-NaCl is done before the start of the process. Compaction and sintering both happen during the course of friction sintering. Scanning electron microscopy (SEM) images of fracture surface indicate that pore morphology is dictated by the morphology of NaCl particles. Temperature increases with the increase in plunge depth. The stress-strain curves for obtained foam in compression are similar to the reported in.
Cutting Process Simulation in Micro Dimple Machining
Authors: Matsumura Takashi , Musha Yuji 
Published: November 2019

Abstract
The paper discusses micro dimple millings with inclined ball end mills. Cutting process models are presented to control the dimple shapes and predict the cutting forces. In micro dimple milling, the cutter rotation axis is inclined to have the non-cutting time, during which the cutting edges don’t remove the material in a rotation of cutter. The end mill is fed at a high rate so that the machining areas removed by the cutting edges are not overlapped each other. The shapes and the alignment of the dimples are simulated for the cutting parameters in the mechanistic model. Then, the cutting forces are predicted for high machining accuracies. The cutting experiments were conducted to verify the micro dimple machining. The dimple shape model is validated in comparison between the simulated and the actual dimple shapes. The cutting forces are simulated to compare the measured ones. The force model works well to predict the cutting forces with the chip flow direction during a rotation of the cutter.