bluuebunny/crossref_metadata_2025 huggingface dataset:
Laser Induced Porosity and Crystallinity Modification of a Bioactive Glass Coating on Titanium Substrates
Authors: Kongsuwan Panjawat , Brandal Grant B. , Yao Y. Lawrence
Published: September 2015

Functionally graded bioactive glass coatings on bioinert metallic substrates were produced by using continuous-wave (CW) laser irradiation. The aim is to achieve strong adhesion on the substrates and high bioactivity on the top surface of a coating material for load-bearing implants in biomedical applications. The morphology and microstructure of the bioactive glass from the laser coating process were investigated as functions of processing parameters. Laser sintering mechanisms were discussed with respect to the resulting morphology and microstructure. It has been shown that double layer laser coating results in a dense bond coat layer and a porous top coat layer with lower degree of crystallinity than an enameling coating sample. The dense bond coat strongly attached to the titanium substrate with a ten microns wide mixed interfacial layer. A highly bioactive porous structure of the top coat layer is beneficial for early formation of a bone-bonding HCA layer. The numerical model developed in this work also allows for prediction of porosity and crystallinity in top coat layers of bioactive glass developed through laser induced sintering and crystallization.
Simulation-Based Electricity Demand Response for Combined Manufacturing and HVAC System Towards Sustainability
Authors: Dababneh Fadwa , Atanasov Mariya , Sun Zeyi , Li Lin
Published: September 2015

In this paper, we introduce a simulation-based method to implement electricity demand response for manufacturers considering both heating ventilation and air conditioning (HVAC) and manufacturing systems. Compared with the existing literature where the demand response implementation for manufacturing system and HVAC system is usually conducted separately, this paper advances the state of the art by combining two systems together in demand response. A joint simulation model is established using ProModel and EnergyPlus. ProModel is first used to simulate the demand response for the manufacturing system to obtain the demand response actions without influencing production. After that, these actions are used as input information in EnergyPlus where the HVAC and building models are developed. The interaction between the heat generated due to manufacturing machine operation and the indoor heat demand is explored. Three different demand response strategies, i.e., 1) the baseline model that neither manufacturing system nor HVAC is considered for demand response; 2) only manufacturing system is considered for demand response; and 3) both the HVAC and manufacturing systems are considered for demand response, are presented and compared. The results show that the combined model can achieve high power demand reduction during demand response event.
Process Parameter Studies of Molecular Dynamics Models to Control Substrate Wettability
Authors: Cordeiro Jhonatam , Desai Salil
Published: September 2015

Nanotechnology is being used to solve many engineering problems in the fields of electronics, medicine and energy. However, nanomanufacturing and nano-characterization of materials usually require time, specialized machinery and laboratory facilities that are unavailable or expensive to operate. The use of classical computer simulation of materials, such as finite element analysis has limited representation at the nanoscale, because they fail to consider the atomic configurations and forces. This research presents the use of Molecular Dynamics modeling to characterize materials at the nanoscale. Atomistic models of Gold and SiO2 were simulated to predict their wettability with nano droplets of water. Results are presented on how the simulation environment influences representation accuracy of the models. Analysis tools, such as geometry measurements and average atomic position variability are used to infer about the wettability of these materials with different surface pattern topologies. The tools, analysis and results presented can be extended to investigate other engineering problems that may have solutions at the nanoscale.
Experimental Investigation on Elastic Spring Back in Deformation Machining Bending Mode
Authors: Singh Arshpreet , Agrawal Anupam
Published: September 2015

Deformation machining is a combination of thin structure machining and single point incremental forming. It enables the creation of thin monolithic structures with complex geometries in one setup, employing conventional manufacturing techniques. Elastic spring back is a major contributor to dimensional inaccuracy of the thin formed structures. Correct prediction of elastic spring back and its compensation is of utmost importance for the overall quality of the formed components. In the present work, an experimental study on elastic spring back in deformation machining bending mode components has been performed. Effect of machining and forming parameters along with dimensional attributes on the elastic spring back has been studied. The components were fabricated using a 3 axis CNC vertical milling machine and inspected for elastic spring back on a coordinate measuring machining (CMM). Other factors contributing to the dimensional inaccuracy, such as curvature in the bent structure and inclination of structure along its length have also been explored.
Shape Memory Composite Hands for Space Applications
Authors: Quadrini Fabrizio , Tedde Giovanni Matteo , Santo Loredana
Published: September 2015

Shape memory composites combine structural properties of continuous-fiber polymer-matrix composites with functional behavior of shape memory polymers. In this study, the production of shape memory composite structures for aerospace applications is described. Small-scale grabbing systems were prototyped as they could be used for space cleaning operations. Composite hands were manufactured by using two carbon fiber composite layers with a shape memory polymer interlayer. They were produced in the closed-hand configuration and subsequently opened in the memorizing step. Due to heating, composites tended to recover the initial closed configuration, allowing to grab small objects. Two different shapes (cylindrical and cubic) were considered for composite hands. In the first case, the shape memory behavior was given to the entire structure whereas, in the second case, shape memory properties were provided only to folding zones. As a result, a good shape recovery was observed in both cases but part weight was already not negligible also in these small-scale systems.
Some Investigations on Surface Texturing on Monel 400 Using Photochemical Machining
Authors: Mudigonda Sadaiah , Patil Deepakkumar H.
Published: September 2015

This paper reports the creation of surface textures using Photochemical Machining Process (PCM) on Monel 400. Machining is carried out on Monel 400 sheets. The influence of the photolithography parameters and spinning speed on the photoresist films were investigated. The etching media used is HNO3:FeCl3:H2O = 30ml: 500g: per liter concentration. The effects of etching time and temperature on the etched topography pattern were studied. It has been observed that time has more influence on the depth of etch as compared to temperature. However temperature influence surface finish more.
Experimental Study on Micro-Grinding Process of Titanium Alloy Using Electro-Hydro-Dynamic Spray With Nanofluid and Compressed Air
Authors: Lee Pil-Ho , Nam Jung Soo , Kim Jung Sub , Lee Sang Won
Published: September 2015

In this paper, the micro-scale grinding processes of titanium alloy (Ti-6Al-4V) using electro-hydro-dynamic (EHD) spray with nanofluid and compressed air are experimentally investigated. In the experiments, specific micro-grinding forces and surface roughness of the ground workpiece are quantitatively analyzed as a function of nanofluid’s concentration and size of nanoparticles. In addition, the ground surface quality is qualitatively investigated by comparing the optical microscopic images. The experimental results show the effectiveness of EHD spraying with nanofluid and compressed air for reducing the specific micro-grinding forces and enhancing ground surface quality.
Surface Topography Separation Based on Wavelet Reconstruction and Empirical Mode Decomposition
Authors: Zhang Faping , Yang Jibin , Zhang Tiguang , Yan Yan
Published: September 2015

Surface topography decomposition used to identify the components of the machined surface is an important method for tracing machining errors and predicting surface performance. This paper presents a generalized and practical method to fulfill the surface topography decomposition by wavelet reconstruction and Empirical Mode Decomposition (EMD). Firstly, by choosing suitable base function, wavelet transformation technique was applied for surface decomposition to get surface components in different level, with some levels containing uncertain information, indicating that wavelet transform was not an ideal method to get genuine components of machined surface. EMD was applied for further decomposition, EMD can obtain genuine components of surface, mode mixing occurred when surface contained noise and impulse. A hybrid method combining the merits of wavelet and EMD was proposed to eliminate noise and impulse in surface, then genuine components of surface was obtained. Finally, the proposed method was applied to a measured 1-D surface, and its genuine components were gotten respectively. Further Fourier Transform was used to confirm the result which indicates that proposed method can correctly get genuine components of the machined surface. The method proposed in this article will give a practical guidance for surface components analysis and provide a base for further study such as tracing processing and predicting performance of surface according its components.
FE Simulation of Cryogenic Assisted Machining of Ti Alloy (Ti6AI4V)
Authors: Bajpai Vivek , Lee Ineon , Park Hyung Wook
Published: September 2015

Titanium alloys are well-known material because of the excellent mechanical/chemical properties, corrosion resistance and light weight. These alloys are widely used in the high performance applications such as; aerospace, aviation, bio-implants, turbine blades etc. Machining is commonly used to create products out of Ti alloys. Despite of good material properties, Ti alloys have low thermal conductivity, poor machinability, burr formation, high machining temperature, tool wear and poor machinability. The tool wear and high machining temperature can be controlled through coolant. Cryogenic fluid (liquid nitrogen) is a common material used as coolant in various machining process. The current work is focused on the modeling of cryogenic machining on titanium alloy (Ti6Al4V). Dry machining and cryogenic machining processes are modeled for the chip formation and cutting forces in 2D. Experimental works have been performed to validate the model based on the cutting forces and chip morphology. It is showed that the model is capturing the process, evident by the cutting forces and the chip morphology. The error in prediction is limited to 18%. Model showed that the cutting forces are increasing in cryogenic machining due to the increased strength of the workpiece at low temperature. Chip formation is well captured by the current model. Shear band width have been captured in dry machining. Chip curling has been captured at dry and cryogenic machining. It is expected that the model can further useful in the selection of cryogenic process parameter, such as, flow rate, application techniques etc.
A Cellular Automata Model for Nitriding of Nanocrystalline Iron
Authors: Zhao Jingyi , Wang G.-X. , Dong Yalin , Ye Chang
Published: September 2015

In this study, a numerical model was developed to investigate the effects of grain refinement on the efficiency of nitrogen diffusion during the nitriding process. A cellular automata (CA) model without considering the effects of grain boundaries was built to simulate the nitriding process. The results from the numerical model were compared and validated by experimental data in the literature. Then, nanoscale grain boundaries were integrated into this CA model. The nitriding efficiency in materials with different grain sizes was investigated. The results demonstrate that nanocrystallization can significantly increase the nitrogen diffusion efficiency and thus make low temperature (300°C) nitriding possible.
Effects of Rotating-Bending and Torsional Fatigue Loads on Gas Tungsten Arc (GTA) Welded AISI 1018 Low Carbon Steel Joints
Authors: Dewan M. W. , González Gustavo , Wahab M. A.
Published: September 2015

Most welded structures are subjected to multiaxial fatigue load and majority of the fatigue failure initiated from weld joints. Therefore, it is important to evaluate multiaxial fatigue behavior of commonly used welded materials. In the current investigations, the influence of rotating bending fatigue load along with torsional pulsed load was appraised for most commonly used AISI 1018 low carbon steel. A rotating-bending-torsional fatigue testing unit was designed and manufactured for biaxial fatigue test of welded and un-welded specimens. For welded specimens, Gas Tungsten Arc welding (also known as Tungsten-Inert-Gas (TIG) welding) was carried out on 19.05 mm diameter round bar of AISI 1018 steel using ER70-S2 filler metal. For rational comparison, only defects-free specimens were carefully chosen and tested. After welding, uniaxial tensile test was conducted to understand the fatigue loading criteria during rotating-bending fatigue test. Due to TIG welding, tensile strength was decreased considerably about 18% as compared to base metal. Rotating-bending (RB) and rotating-bending-torsional (RBT) fatigue tests were conducted to obtain a systematic understanding of biaxial fatigue behavior. RB fatigue life of welded specimens reduced compared to base metal as a result of complex thermal cycle during welding process and microstructural changes. Under combined loading conditions (RBT), base metal specimens did not exhibit significant difference on the fatigue behavior. However, for the welded specimens, the fatigue strength was reduced by about 12.8%. Moreover microstructural characterization and fracture surface analysis were performed to understand the fracture behavior of the tested specimens.
Scratch Tests on Granite Using Micro-Laser Assisted Machining Technique
Authors: Mohammadi Hossein , Patten John A.
Published: September 2015

In this study, micro-laser assisted machining (μ-LAM) technique is used to perform scratch test on a granite sample. Rocks are generally considered as brittle materials with poor machinability and severe fracture can be resulted when trying to cut them due to their low fracture toughness. Due to increasing demand for these materials in industry with many applications, finding a fast and cost effective process with higher product quality seems essential. In past research in our research group, it has been demonstrated that machining of brittle materials such as semiconductors and ceramics in ductile regime is possible due to the high pressure phase transformation (HPPT) occurring in the material caused by the high compressive and shear stresses induced by a single point diamond tool tip. Scratch tests were performed on the granite sample and to further augment the process, traditional cutting is coupled with the laser to soften the material and get the higher depth of cut. In this research, results of scratch tests done on granite, with and without laser heating have been compared. The effect of laser heating was studied by verifying the depths of cuts for scratch tests with varying the laser power during the process. Microscopic images and three-dimensional profiles of cuts taken by using a white light interferometer were investigated. Results show that using laser can increase depth of cut and with 15 W laser power it is increased — for different regions of granite sample — from 25% to 95%.
Ultrasonic-Assisted Dilute Acid Pretreatment of Poplar Wood Biomass for Biofuel Manufacturing: A Preliminary Study
Authors: Song Xiaoxu , Zhang Meng , Pei Z. J. , Wang Donghai
Published: September 2015

For the first time, this study demonstrated that the efficiency of enzymatic hydrolysis of poplar wood biomass was drastically enhanced after being pretreated with ultrasonic-assisted dilute acid pretreatment comparing to dilute acid pretreatment only. Three levels of ultrasonic power (0%, 30%, and 70%) were used in pretreatment. Approximately 10–40% improvement in the sugar yield was attained by using ultrasound-assisted dilute acid pretreatment for 15 min. XRD analysis revealed that poplar wood biomass pretreated ultrasonically had lower biomass crystallinity than that pretreated with dilute acid only. The combination of ultrasound irradiation and dilute acid can be a key factor in the disruption of rigid cellulose structures and contributes to the improvement of cellulose saccharification in enzymatic hydrolysis.
Vibration Needle Tissue Cutting With Varying Tip Geometry
Authors: Barnett Andrew C. , Feidner Malorie , Moore Jason Z.
Published: September 2015

Needles are one of most commonly used medical devices. They are used to deliver drugs, biopsy tissue, draw blood, conduct brachytherapy cancer treatment and many other procedures. Maintaining a low insertion force of the needle is important to the success of these procedures. Different geometries as well as utilizing vibratory cutting has been shown to reduce the insertion force, thus improving the outcome of the procedure; however, the effects of vibration and geometry of the needle together has yet to be explored. This paper describes the experimental setup utilized to test the effect of geometry on utilizing axial vibration in reducing the insertion force of needles into bovine liver across a range of frequencies and amplitudes. Three conical tipped needles with different grind angles were explored. Experiments showed the addition of the vibration was able to reduce the insertion force by up to 67%. Experiments showed that the insertion force for the bluntest needle was directly dependent on the amplitude of vibration, where the insertion force of the sharpest needle was more dependent on the maximum vibratory insertion speed of the needle.
A Generalized Data-Driven Energy Prediction Model With Uncertainty for a Milling Machine Tool Using Gaussian Process
Authors: Park Jinkyoo , Law Kincho H. , Bhinge Raunak , Biswas Nishant , Srinivasan Amrita , Dornfeld David A. , Helu Moneer , Rachuri Sudarsan
Published: September 2015

Using a machine learning approach, this study investigates the effects of machining parameters on the energy consumption of a milling machine tool, which would allow selection of optimal operational strategies to machine a part with minimum energy. Data-driven prediction models, built upon a nonlinear regression approach, can be used to gain an understanding of the effects of machining parameters on energy consumption. In this study, we use the Gaussian Process to construct the energy prediction model for a computer numerical control (CNC) milling machine tool. Energy prediction models for different machining operations are constructed based on collected data. With the collected data sets, optimum input features for model selection are identified. We demonstrate how the energy prediction models can be used to compare the energy consumption for the different operations and to estimate the total energy usage for machining a generic part. We also present an uncertainty analysis to develop confidence bounds for the prediction model and to provide insight into the vast parameter space and training required to improve the accuracy of the model. Generic parts are machined to test and validate the prediction model constructed using the Gaussian Process and we consistently achieve an accuracy of over 95 % on the total predicted energy.
Experimental Investigations to Evaluate the Performance of Alternate Striped Coated Carbide Inserts in Turning of AISI 1040 Steel
Authors: Chilamkurti L. V. R. S. V. Prasad , Puvvada Naga Lakshmi Pavani , Koona Ramji , Swarna Venkata Ramana
Published: September 2015

During machining in order to improve the performance of the tool, it is necessary to have a clear understanding of chip flow and chip-tool interactions on the rake face. The predominating factors which influence the performance of cutting tool are proper combinations of process variables, tool and workpiece. Focusing more on environmental and economic considerations, dry machining is preferred in the present work to study and evaluate the performance of the multi-striped alternate coated Tungsten Carbide (WC) inserts. Dry turning tests on AISI 1040 steel at various machining conditions have been carried out using uncoated and striped coated cutting tools to deliberate the wear patterns close to the cutting edge. An effective tool coating helps the tool manufacturers to increase the tool life during high speed machining conditions. In the earlier research, in evaluating the performance of single and multi-layer carbide tools, tool wear has been considerably reduced in multi-layer coated tools compared with single layer coated tools. In the current work, to further reduce the tool wear an attempt has been made to assess the tool wear with striped coated carbide tools having alternate bands of hard and soft coatings located close to the cutting edge. The findings are significant in the current study which shows that no crater wear has been observed. Further authors also tried for the optimum rake face utilization by having the proposed band of coatings close to the cutting edge.
Optimal Blank Shape Prediction Considering Sheet Thickness Variation for Multistage Deep Drawing
Authors: Agrawal Anupam , Reddy N. Venkata , Dixit P. M.
Published: September 2015

Deep drawing is one of the very old and widely practiced processes in the sheet metal industries for producing beverage cans and automobile components. Many of the deep drawn components need multiple draws to achieve the required dimensions, because often it is not possible to obtain the desired reduction in the first draw. Among several defects that occur during the process, earing is one of the prominent and common defect. In the present work, analysis has been carried out by dividing the total deformation region into several zones. Analysis of each zone is carried out by proposing kinematically admissible velocity field, i.e. the velocity field satisfying the condition of normal velocity continuity and volume constancy. The input material (already drawn cup) for redrawing is pre-strained from the previous stage drawing operation and this has been considered while carrying out the analysis. Thickness and punch load predictions are validated by comparing them with the published results and are found to be in good agreement. The optimal blank shape, that will result in earing free cup after the final drawing operation, has been determined. For the prediction of optimal blank shape for multistage deep drawing, addition-subtraction scheme has been developed and successfully implemented; the modification of the initial blank is done after each stage of drawing. The optimal blank shape obtained has been tested, using simulation, to draw the cup and it yields the final cup height with percentage earing less than 1%. However, in a few cases, three or four iterations for the modification of blank may be required, to bring the percentage earing within the specified limit.
Process and Production Planning in a Cloud Manufacturing Environment
Authors: Lu Yuqian , Xu Xun
Published: September 2015

Cloud manufacturing provides a way for manufacturing companies to rapidly form a flexible production network to respond to the growing demand of highly personalised products. Computer-aided Process Planning (CAPP) is an important element of production planning. However, existing methodologies failed to meet the requirements for CAPP systems in the cloud, which is a distributed, collaborative, and web-based environment. This paper discusses the requirements of CAPP systems in a cloud environment and proposes a feasible system framework for next-generation CAPP systems. The proposed system is built upon Service Oriented Architecture (SOA) architecture, which enables smooth system integration among different manufacturers. A two-stage strategy for generating feasible production plans for a given manufacturing request is discussed in this paper. Moreover, a feasible mechanism to incorporate shared engineering practices and knowledge from each manufacturer is also presented as part of the proposed system.
Impact of Additive Manufacturing Adoption on Future of Supply Chains
Authors: Mashhadi Ardeshir Raihanian , Esmaeilian Behzad , Behdad Sara
Published: September 2015

Although separation of product design from manufacturing capabilities is a major advantage of Additive Manufacturing (AM), the impact of AM is not only limited to the design and manufacturing stages. In addition to the freedom of design such as elimination of design constraints, material saving, and free complexity, AM offers other potential benefits to the manufacturing industry as well. One of the most immediate potentials of AM is the possibility of more efficient logistics. This paper aims at describing the characteristics and requirement of a Supply Chain (SC) as well as the changes AM will bring into the current structure of supply chain. Insights are provided on the transformative effects of AM on traditional businesses, and how these changes impact the configuration of a supply chain. The potential for using simulation tools to evaluate AM supply chain have been discussed. Further, two examples of Agent Based Simulation (ABS) and System Dynamics (SD) have been provided to show the application of simulation models. The ABS results show the possibility of lead time reduction in AM based supply chain. In addition, the SD model illustrates the potential for less ‘pipeline’ effect in AM compared to traditional supply chain.
Effects of Process Variables on Extrusion of Carbon Fiber Reinforced ABS Filament for Additive Manufacturing
Authors: Hull Emmett , Grove Weston , Zhang Meng , Song Xiaoxu , Pei Z. J. , Cong Weilong
Published: September 2015

Additive manufacturing (3D printing) is a class of manufacturing processes where material is deposited in a layer-by-layer fashion to fabricate a three-dimensional part directly from a computer-aided design (CAD) model. With a current market share of 44%, thermoplastic-based additive manufacturing such as fused deposition modeling (FDM) is a prevailing technology. A preliminary extrusion process is required to produce thermoplastic filaments for use in FDM 3D printers. It is crucial that extruded filament must have constant dimensional accuracy for FDM 3D printers to produce the desired object with precision. In this study, carbon fibers were blended with acrylonitrile butadiene styrene (ABS) thermoplastics to produce carbon fiber reinforced ABS filaments in order to improve the mechanical properties of FDM-printed objects. During filament extrusion, three process variables showed significant effects on filament diameter, expansion percentage, and extrusion rate. These process variables included carbon fiber content, extrusion temperature, and nozzle size. The objective of this study is to test the feasible ranges of these process variables and to investigate their effects on filament extrusion. Results of this study will provide knowledge on quality improvement of carbon fiber reinforced ABS filament extrusion for additive manufacturing.
Investigation of Acoustic Signals During W1 Tool Steel Quenching
Authors: Nikhare Chetan P. , Ragai Ihab , Loker David , Sweeney Shannon , Conklin Chris , Roth John T.
Published: September 2015

Quenching is an important part of the heat treatment process for strengthening medium and high carbon steels. In the heat treatment cycle, the metal is heated to a desired temperature (above the eutectoid temperature) in the furnace and then cooled in a fluid medium such as water, brine, oil or air. Depending on the cooling rate, the mechanical and metallurgical properties of the metal can be altered in order to achieve the specific design parameters that are required by the part. The process in which the metal is cooled rapidly is termed the quenching process. Due to rapid cooling in a medium, such as water, brine, or oil, the quenching process produces an audible sound signature, as well as, acoustic emissions. In this paper, W1 tool steel is investigated through the use of a beam former that is equipped with 32 microphones. Using this device, it is demonstrated that the audible sounds that are produced when quenching depend on the heat treatment temperature and the size of the specimen.
Detailed Analysis and Description of Grinding Wheel Topographies
Authors: Weiß Markus , Klocke Fritz , Barth Sebastian , Rasim Matthias , Mattfeld Patrick
Published: September 2015

In this paper, an innovative approach for the description of the functional properties of a grinding wheel surface is discussed. First, the state of the art in the description of grinding wheel topographies is summarized. Furthermore, the fundamentals for a new approach for the quantitative description of grinding wheel topographies are provided. In order to analyze the functional properties of a grinding wheel’s topography depending on its specification, grinding experiments were carried out. For the experimental investigations both vitrified and synthetic resin bonded grinding wheels with varied compositions were analyzed.

During the experiments, the topographies of the investigated grinding wheel surfaces have been analyzed in detail. The developed software tool allows for a detailed description of the kinematic cutting edges depending on the grinding process parameters and the grinding wheel. In addition to the calculation of the number of kinematic cutting edges and the area per cutting edge a differentiation of the cutting edge areas in normal and tangential areas of the grinding wheel’s circumferential direction is implemented. This enables a detailed analysis and a quantitative comparison of grinding wheel topographies related to different grinding wheel specifications. In addition, the influence of the dressing process and wear conditions can be evaluated. The new approach allows a better characterization of the contact conditions between grinding wheel and workpiece. Hence, the impact of a specific topography on the grinding process behavior and the grinding result can be revealed.
Study of the Degradation of Polyethylene Glycol in Inconel 718 Feedstock During Powder Injection Moulding Process
Authors: Royer Alexandre , Gelin Jean-Claude , Barrière Thierry
Published: September 2015

Metal injection moulding (MIM) has over the past decade established itself as a competitive manufacturing process to produce in large quantities small precision components with complex shape which would be costly to produce by alternative methods (Enneti, 2012). MIM is a process which combines the versatility of plastic injection moulding with the strength and integrity of machined, pressed or otherwise manufactured small, complex metal parts. MIM consist in shaping powder particles in injection process and then sintering them. MIM make use of the plastic moulding concepts to shape powder-polymer feedstock into the required geometry. During the injection phase, segregation appears in the feedstock and defects will be appear in the component during the sintering. To limit this effect a vast variety of binder systems have been developed (Enneti, 2012) to improve the homogeneity of feedstocks and limit segregation. Binder is formulated as a mixture of different organic or inorganic substances with several functions. Binder has the main commitments of giving the necessary rheological behavior to the feedstocks for injection moulding to transport the powder particles into the mould cavity and the cohesion of the green part (Enneti, 2012).

The goal of this study is to characterize and understand the chemical behavior of feedstocks during the phases of mixing and injection. First the binder was studied. Then based on these results the characterization of the feedstock was made. For this a study of the chemical behavior and interactions on feedstocks based on polyethylene glycol (PEG) and Inconel 718 powder was investigated by Fourier Transform InfraRed spectroscopy (FTIR) (Hidalgo et al., 2013). That methodology was also investigated to study the thermal behavior of the binder at a temperature close to the temperature of mixing and injection. Analyzes shows the thermal degradation of the PEG is not affect by the components of the feedstocks. No chemical interactions between the powder and the binder are revealed. The thermal degradation of the PEG appears during the mixing process and change the rheological behavior of the binder. This result shows the necessity to develop another formulation of binder to preserve the PEG.
Evaluation of the Working Surface of the Grinding Wheel Using Speckle Image Analysis
Authors: Narayanaperumal Arunachalam , Lakshmanan Vijayaraghavan
Published: September 2015

The surface quality of the ground components mainly depends on the surface condition of the grinding wheel. The surface condition of the grinding wheel changes with grinding time due to wheel wear and loading. The excessive wear and loading increases the cutting force and the temperature. This in turn affects the quality of the produced component. Hence periodic monitoring of the grinding wheel surface is essential to avoid the production of the defective components. In this paper, an attempt is made to study the changes in the grinding wheel surface condition using the laser scattered images. The simple speckle imaging arrangement is fabricated and fitted into the grinding machine to capture the images of the grinding wheel after each 100 passes. The fresh wheel expected to scatter more light due to higher roughness and porosity. On the other hand, the completely glazed and worn-out wheel scatters the light less due to smoother surface. Thus, speckle image intensity distribution captures the changes in the grinding wheel surface condition. The optical parameters evaluated from the speckle images clearly indicating the changes in the grinding wheel condition. This method can be utilized to evaluate the grinding wheel condition to improve the surface quality of the component produced.
An Anomaly Detection and Diagnosis Method Based on Real-Time Health Monitoring for Progressive Stamping Processes
Authors: Shui Huanyi , Jin Xiaoning , Ni Jun
Published: September 2015

Progressive stamping processes have been applied to fabricate an extended range of products from centimeter-scale parts to meter-scale parts. The quality of stamped products may vary and be out of specification due to various anomalies during manufacturing process. Therefore, an effective online health monitoring and fault diagnosis technique is of great practical significance. This paper develops a two-stage systematic approach to enhance the fault detection and fault identification capability for the progressive stamping process with aggregated system-level tonnage signals. The first stage uses a combined Haar transform and power spectrum analysis to map features extracted from aggregated signals to individual operations. The second stage develops a two-step control chart strategy for anomaly detection and identification. The proposed method can improve the monitoring effectiveness and the quality assessment of individual operations based on an aggregated tonnage signal especially when single working range of different operations in the multi-station system are highly overlapped. The results show the method efficacy of quick and accurate anomaly detection and identification in real time.
Supporting Affordability-Based Design Decisions in the Presence of Demand Variability
Authors: Siedlak Dennis J. L. , Schlais Paul R. , Pinon Olivia J. , Mavris Dimitri N.
Published: September 2015

In the years since the Cold War, the aerospace industry has seen a shift towards affordability-based design from the primarily performance-based designs of the past era. While many techniques, such as IPPD and PLM, have been implemented in support of this shift, recent developments in the industry have led to major cost overruns and production delays. The increased prevalence of demand variability in the aerospace industry and the difficulty to rapidly adapt production plans are a primary cause of these issues. Furthermore, traditional aircraft designers perform detailed manufacturing cost analysis late in the design process when the majority of the program costs are already committed. With the recent shift to more composite aerostructures, historical regressions and cost estimating relationships used to predict cost and manufacturability are no longer accurate, so postponing more detailed cost analyses to later design phases can lead to high costs due to sub-optimal early design decisions. The methodology presented in this paper addresses these problems by providing the ability to conduct multi-disciplinary trades in the early stages of design, when a large amount of design freedom and cost savings opportunities exist.

To enable these multi-disciplinary trades, this paper describes how aircraft performance considerations are integrated with production rate, manufacturing cost, and financial planning metrics into a parametric, visual trade-off environment. The environment, combined with a multi-objective optimization routine, facilitate effective affordability-based trades during the early stages of design. An F-86 Sabre redesigned wingbox using 3 separate manufacturing concepts is used as a proof-of-concept for this research.
Tool Wear Monitoring for Ultrasonic Metal Welding of Lithium-Ion Batteries
Authors: Shao Chenhui , Kim Tae Hyung , Hu S. Jack , Jin Jionghua (Judy) , Abell Jeffrey A. , Spicer J. Patrick
Published: September 2015

This paper presents a tool wear monitoring framework for ultrasonic metal welding which has been used for lithium-ion battery manufacturing. Tool wear has a significant impact on joining quality. In addition, tool replacement, including horns and anvils, constitutes an important part of production costs. Therefore, a tool condition monitoring (TCM) system is highly desirable for ultrasonic metal welding. However, it is very challenging to develop a TCM system due to the complexity of tool surface geometry and a lack of thorough understanding on the wear mechanism. Here, we first characterize tool wear progression by comparing surface measurements obtained at different stages of tool wear, and then develop a tool condition classification algorithm to identify the state of wear. The developed algorithm is validated using tool measurement data from a battery plant.
Robustness of 802.15 Wireless Interface for Real-Time Thermal Feedback Control of the Friction Stir Welding Process
Authors: Kruger Grant H. , Miller Scott F. , Shih Albert J. , van Niekerk Theo I.
Published: September 2015

Friction Stir Welding (FSW) is a modern, solid-state joining processes, involving frictional heating and mechanical forging. High quality joints can be created using a control system that compensates for external disturbances by regulating the state of the weld zone (WZ) surrounding the tool. However, in this situation direct monitoring is complex since the rotating tool is embedded in plasticized material.

This research discusses the development of a Bluetooth-based Wireless Rotating Process Monitoring (WRPM) system to overcome limitations in inductive/capacitive telemetry systems. Communication channel performance was assessed to determine the suitability of Bluetooth for use in the feedback control loop for in-process FSW WZ temperature control.

Peak round-trip communications latencies of 300–650 ms for 20–200 byte payloads were observed. Additionally, electrical noise from the machine tool reduced the receive signal strength measured on the Bluetooth module. The bit error rate (BER) also increased from 0 to 0.001 % as spindle speed increased from 0 to 1400 rpm. Due to the communication latency, the signal strength and BER effects were not observed to affect throughput. The results support the use of the WRPM system for feedback control of FSW. However, deterministic communication latency must be achieved to enable the design of a stable control system.
Incrementally Formed Stiffeners Effect on the Reduction of Springback in 2024-T3 Aluminum After Single Point Incremental Forming
Authors: Ruszkiewicz Brandt J. , Dodds Sean S. , Reese Zachary C. , Roth John T. , Ragai Ihab
Published: September 2015

Single Point Incremental Forming (SPIF) is a relatively new process to form sheet metal. SPIF utilizes machines such as CNC’s and mills to form a part by making several spiraled passes, deforming the metal a certain distance, known as the step-size, with each pass. One major issue with this process is global springback. Once the metal is removed from its clamping fixture, the residual stresses that resulted from the forming process cause the material to springback. The purpose of this paper is to demonstrate how incrementally forming a stiffener on the outside of the desired geometry will manipulate the stress concentrations in the metal, and effectively reduce the amount of global springback that occurs after the specimen is unclamped from its fixture. For these tests, stiffeners were formed on the outside of a truncated pyramid; the material used for these test was 2024-T3 aluminum. After the work pieces were removed from their clamping fixtures, the amount of springback that they experienced was examined using Geomagic software to determine the ideal stiffener parameters for reducing global springback for a truncated pyramid in 2024-T3 aluminum.
Numerical Analysis of the Effect of Non Uniform Electric Field on the Trajectory of Micro Water Jet
Authors: Mohanty Satyabrata , Ehmann Kornel F. , Cao Jian
Published: September 2015

In spite of its inherent advantages as a manufacturing tool, water-jet has not been extensively applied to the field of micro-manufacturing due to its low tolerance and poor control of the position of jet impingement. This paper explores the possibility of using the phenomenon of liquid dielectrophoresis to deflect and control the trajectory of a water jet in air. An approach is suggested using a localized non-uniform static electric field over a micro water jet with diameters in the range of 25–100 micrometers. The water jet has been modelled as a thin dielectric column and the numerical analysis of the electric field distribution has been carried out using COMSOL to analyze the generated forces and predict the scale of deflection of the jet. This unique approach of harnessing the polar nature of water using the phenomenon of dielectrophoresis might be useful in achieving fine control of the water jet’s trajectory especially in micro water jet material processing.
Design for Manufacturability in Additive Manufacturing Using a Graph Based Approach
Authors: Ranjan Rajit , Samant Rutuja , Anand Sam
Published: September 2015

Additive Manufacturing (AM) processes are used to fabricate complex parts using a layer by layer approach. This enables designers to be more creative with their designs and build parts which may be difficult to manufacture using conventional processes. However, as AM is in its infancy, relevant literature with respect to design guidelines for AM is not readily available. This research proposes a novel approach to implement design guidelines in AM using a systematic graph based approach. These design rules will assist designers to come up with efficient part designs that can be manufactured with minimum part errors. The design rules are formulated by studying the relationship between input part geometry and AM process parameters. A feature graph based design analysis method is proposed along with a Producibility Index (PI) which is used to compare the designs. Modifications in part design based on these rules and their comparison is presented in the form of three case studies.
Prediction of Residual Stress in Multi-Step Orthogonal Cutting
Authors: Shao Yamin , Fergani Omar , Welo Torgeir , Liang Steven
Published: September 2015

The effect of residual stresses on the fatigue behavior as well as the dimensional stability of high precision part is very important. Machining operation consists generally multi-step operations from roughing to finishing. It is therefore critical to predict residual stresses under such configuration. In this paper, an analytical algorithm is proposed to predict the final residual stresses induced by a multi-step machining operation capturing the change of stress state of the workpiece as well as material hardening behavior during the multi-step orthogonal cutting. The model predictions were compared to other work’s finite element method (FEM) predictions.
Study of Plunge Stage for a Hybrid Friction Stir Welding Process Based on Electro-Plastic Effect
Authors: Liu Xun , Lan Shuhuai , Qiao Xianli , Ni Jun
Published: September 2015

In this study, an electrically assisted friction stir welding (FSW) system has been designed and developed. Additional electrodes are assembled and stay in the close proximity of the tool as the tool translates along the weldline. Plunge stage of FSW process has been studied for both aluminum alloy Al 6061 and TRIP 780 steel based on this developed experimental configuration. An effective axial force reduction can be consistently observed after application of a continuous current. In order to compare the relative significance of the associated resistance thermal effect, the workpiece has been preheated to approximately same temperature and it can be shown that around 2/3 of the force reduction can be contributed to the electricity itself. Microstructure of the cross sections for Al 6061 plunge specimens indicated an enhanced dynamic recrystallization process under the influence of current. This phenomenon was not obvious on steel, which is probably due to the higher Joule heating temperature and consequently accelerated grain growth. On the other hand, thermal mechanically affected zone of steel suggested a retarded martensitic phase transformation with electrical current applied.
4D Printing: Design and Fabrication of 3D Shell Structures With Curved Surfaces Using Controlled Self-Folding
Authors: Deng Dongping , Chen Yong
Published: September 2015

Self-folding structures such as origami-based structures have been studied by artists, mathematicians and engineers. New applications are emerging in fields such as biomedical and electronics. Self-folding structures can potentially extend three-dimensional (3D) printing into four-dimensional (4D) printing by intelligently designed material distribution in order to achieve controlled shape deformation over time. Traditionally, self-folding structures are folded along pre-defined hinges such that neighboring facets can transform their shapes. In this study, we present a new design and fabrication approach of self-folding structures with no foldable hinges. A significant benefit is its capability in fabricating shapes with smooth curved surfaces.

Our self-folding method is based on a thermally responsive mechanism, where a thermal responsive film is used as the active material while another polymer material coated on the film is used as the constraining material. When the structure is heated, the two sides of the film will shrink differently due to the constraining material. Consequently the structure will fold. By changing the constraining patterns and coated material properties, the film can be self-folded into different shapes. Three types of folding features are presented in our study. Based on them, an unfolding algorithm is presented for a given shell structure with curved surfaces. Theoretical analysis and experimental tests are presented to demonstrate the capability of the self-folding method. Its limitation and future work are also discussed.