bluuebunny/crossref_metadata_2025 huggingface dataset:
Towards a Design Framework for Bi-Level Estimation of Turning Energy for Parts and Assemblies
Authors: Huang He , Ameta Gaurav
Published: September 2010

This paper presents a computational framework for calculating turning energy for parts and assemblies, at two levels — early design stage and manufacturing stage. At the early design stage such energy estimation can be used to redesign the part and assemblies for manufacturing energy efficiency. At the manufacturing stage, allocation of resources based on energy efficient process planning and scheduling aids in reducing the carbon emissions of the product due to manufacturing energy production. For computing the turning energy, at the early design stage, first removal volume for turning operations for a part is identified. Then, material data and the removal volume are used to calculate a range of turning energy for manufacturing the part. If dealing with an assembly, then the above computations are applied to each individual parts and total turning energy is computed for the assembly. Energy hogging parts/features are identified based on percent contribution, which is then used to suggest parts for re-design. Application of statistical analysis and allocation of turning energy for identifying re-design parts is also explored. Re-design at the early design stage is performed at two levels — form (geometry and shape) and material. At the manufacturing stage, turning energy calculations can be utilized for optimizing the process plans. Although the framework presented in this paper is applied only to turned parts and assemblies, it can also be applied to machined parts and assemblies.
Simulation of Solidification Defects for Prediction of Dross Formation in Aluminum 5182 Remelt Secondary Ingot
Authors: Rakita Milan , Han Qingyou
Published: September 2010

In aluminum recycling about 4% on average is lost on oxidation and dross. However, large percent of remelt secondary ingots (RSI) produce much more dross after remelting. It is rather surprising that no dross can be detected in the RSI, but after remelting some parts of apparently ‘healthy’ aluminum can give up to 80% of dross. This raises question how dross gets formed. Recent research proposes that the formation of dross after remelting of the RSI is closely related to the solidification process in the ingot, specifically the formation of shrinkage porosity, hydrogen porosity, and hot tearing. Under these circumstances, dross comes from oxidized surfaces of those defects. In this paper, simulations of the RSI cooling down show susceptibility of ingots towards shrinkage porosity and hot tearing, which are in accordance with experimental findings. Simulations also show that dross is more likely to form with increased temperature of the mold and increased thickness of the ingot. The only efficient solution for the problem of dross formation, however, seems to be a change in geometry of the mold.
Compact Assembly Machine for Cellular Phone Lens Module Using Self-Adjustment
Authors: Lee Jae Hak , Song Jun-Yeob , Lee Chang-Woo , Ha Tae Ho , Jeong Yeong Sang
Published: September 2010

Efficient alignment method using self-adjustment and lens aberration reduction method using several lenses with different orientation for cellular phone lens assembly are introduced to compensate for alignment error among lens parts and minimize lens aberration caused by lens defect in this work, respectively. Self-adjustment module has 2 degrees of freedom of translation motion and 3 degrees of freedom of rotation by porous air bearing and spring to compensate for alignment error automatically. The allowable alignment error and proper inserting force to assembly lens parts successfully was investigated and evaluated compared to conventional lens assembly machine and also optimum orientation of each lens to minimize lens aberration is examined through experiment. Self-adjustment module guarantees accurate arrangement of lens parts during assembly process in spite of alignment error so that remarkable price reduction and miniaturization of assembly machine could be achieved.
Study of Sound Signal for Tool Wear Monitoring System in Micro-Milling Processes
Authors: Chen Tin-Hong , Lu Ming-Chyuan , Chiou Shean-Juinn , Lin Ching-Yuan , Lee Ming-Hsing
Published: September 2010

The modeling of tool wear effect on micro tool vibration and associated sound generation in the milling process was proposed and analyzed first for sound based micro tool monitoring. The LVQ based algorithms, as well as Fisher Linear Function, were also implemented for verify the sound signal capability for monitoring the tool wear condition in micro milling. Micro end-mills of 700 μm in diameter, a high speed spindle up to 60000 rpm, and sensors were installed to investigate the micro tool wear effect on the cutting system and provide the signals for modeling and system capability verification. Multi-sensor signals including the audible sound, cutting force and vibration were collected simultaneously during cutting processes. The simulation results were compared to experimental results and show good correlation to the collected sound signal. With the training and test sound signals collected in experiment, the classifier systems were established and the capability of sound based system were confirmed for detecting micro tool wear successfully.
Dynamic Simulation of Temperature Field in Hybrid Laser-GTAW Welding of Galvanized Steels in a Gap-Free Lap Joint Configuration
Authors: Yang Shanglu , Kong Fanrong , Forroozmehr Ehsan , Kovacevic Radovan
Published: September 2010

During hybrid laser-arc welding of galvanized dual phase steel 980 in a gap free lap joint configuration, the welding parameters have the significant influences on the weld quality, which is directly related to the temperature distribution of welds. In this paper, a 3D FEM model is used with the application of the double ellipsoidal moving heat source to simulate the transient temperature field and the dimensions of fusion zone and heat affected zone (HAZ) for hybrid laser-arc keyhole welding of galvanized steels in a gap-free lap joint configuration. Temperature-dependent thermophysical properties are used in the simulation. Effects of various welding parameters on the temperature distribution are studied. To validate the numerical results, a high-speed camera with the frame rate of 4000 fps is used to real-time capture the images of the molten pool. The numerical results show a good agreement with the experimental results.
Shape Factors and Feasibility of an Industrial Product Through Sheet Metal Hydroforming
Authors: Del Prete A. , Papadia G.
Published: September 2010

Sheet metal hydroforming has gained an increasing interest around the world in automotive and aerospace industries. This non conventional metal forming process has many advantages that meet industrial needs in reality very well, such as: formability improvement, good surface quality, higher dimensional accuracy, reduction of springback amount compared with the conventional processes (1). Furthermore, the process chain could be simplified with considerable cost efficiency (2, 3). Through a research program, whose objective is to define specific rules in order to assess a macro-feasibility for a given hydroforming process, the authors have analyzed the influence of the process variables on sheet metal hydroforming by taking into account different types of geometries. The goal of this research, as described in this paperwork, is to implement a methodology that allows one to check the ‘macro’ feasibility of a product through sheet metal hydroforming starting from simple considerations in the early stage of the process design (4). In this specific case, the developed methodology is characterized by the definition of a set of specifically designed ‘shape factors’ and by their application on properly designed study cases. Their application can determine the feasible limits for a considered process set up condition. The definition of the shape factors and of each of their lower bounds has been drawn through an extensive numerical and experimental investigation on three different study cases which have been described in recent publications by the same authors (5, 6 and 7). In this paper the authors aim to describe and to check the developed methodology through ‘Fondello Fanale’, an application on an industrial test case characterized by a complex geometry. Starting from the geometry of the industrial test case, one can say that it is necessary to use more than one of the defined shape factors to analyze the product feasibility. On the considered component, the most critical areas have been chosen and the geometrical gradients of the shape have been taken into account by the authors. In each one of the considered areas, shape factors have been calculated and their value has been compared to their physical limits for the considered material and thickness. Thorough numerical and experimental investigation the shape factors analysis has given the opportunity to check the non-feasibility of the product. Further developments are related to the possibility, starting from the minimum values of the analyzed shape factors, to redesign the geometry of the product in order to reach its feasibility.
Effects of Ultrasonic Assisted Grinding on CBN Grinding Wheels Performance
Authors: Tawakoli Taghi , Azarhoushang Bahman
Published: September 2010

The effects of ultrasonic assisted grinding on vitrified CBN grinding wheels performance have been investigated. The ultrasonic vibration has been superimposed to the workpiece in feed and cross feed directions and the kinematics of the process in both directions have been discussed. The obtained results show that applying ultrasonic vibration to the grinding process can improve the quality of the workpiece surface, the efficiency of the process and decrease the grinding forces and specific energy considerably.
A Comparative Study of Metamodeling Techniques for Predictive Process Control of Welding Applications
Authors: Ely G. Ray , Seepersad Carolyn Conner
Published: September 2010

Metamodeling is investigated as a tool for predictive process control of welding applications. The motivation for predictive process control is to incorporate physics-based models in place of empirical models that are statistically derived from repeated physical tests. Predictive process control promises to be particularly useful for high flexibility applications, such as frequent modifications of material or geometry. One of the primary challenges is that accurate physics-based, thermal models of the welding process usually require computationally expensive software such as FLUENT [1], while faster models, such as the analytical models of Rosenthal [2], are typically less accurate. Metamodeling or surrogate modeling is investigated as an alternative modeling technique for combining the accuracy of the detailed models with the speed of the faster models, thereby enabling real-time control of the welding process. Four of the most promising metamodeling techniques—polynomial regression, multivariate adaptive regression splines, kriging, and support vector regression—are selected based on a set of preliminary criteria. Each technique is used to build surrogate models of a representative welding process, based on FLUENT data obtained with statistically designed experiments. The techniques are compared with respect to accuracy, speed of model construction, and speed of prediction. Implications for predictive process control of a welding process are also discussed.
FEM Simulation and Experimental Investigation of Reshaping of Thick Tubes in Different Passes
Authors: Tajyar A. , Abrinia K.
Published: September 2010

Recent advances in high temperature and high pressure applications have made significant increase in industrial applications of square and rectangular seamless tubes. In this work, a reshaping process is presented with cold rolling of a circular thick tube into a square cross section between four flat rolls in different passes. The influence of the amount of roll gap reduction in each pass on the final rolled product was investigated. In order to verify the simulation results, several experimental tests were performed. Quantities such as separated force energy, wall thickness, and corner radius of the tube were observed and measured. Obtained results of simulation showed good agreements with the experiment results.
Ultrasonic Vibration Assisted Pelleting of Cellulosic Biomass: A Preliminary Experiment
Authors: Pei Z. J. , Wang Donghai , Clark Robert
Published: September 2010

Biofuels produced from cellulosic biomass (such as the fibrous, woody, and generally inedible portions of plant matter) can significantly reduce the nation’s dependence on foreign oil, create new jobs, improve rural economies, reduce greenhouse gas emissions, and improve national security. However, in the U.S., there are currently no cellulosic biofuel plants in commercial production. Several technical barriers have hindered large-scale cost-effective manufacturing of cellulosic biofuels. One such barrier is related to the low density of cellulosic feedstocks, causing their transportation and storage to be very expensive. Pelleting biomass can increase the overall efficiency by utilizing existing transportation infrastructure and storage systems for mega-ton quantities. If biomass is pelleted, it can be handled and transported with existing grain handling equipment in the field, on the road, and at the central biorefinery. This paper presents experimental study on ultrasonic vibration assisted pelleting of cellulosic feedstocks. The results show that ultrasonic vibration assistance could increase the mechanical strength of pellets by more than six times and the density by 50%.
Force Analysis, Mechanical Energy and Laser Heating Evaluation of Scratch Tests on Silicon Carbide (4H-SiC) in Micro-Laser Assisted Machining (µ-LAM) Process
Authors: Shayan Amir R. , Poyraz Huseyin Bogac , Ravindra Deepak , Ghantasala Muralidhar , Patten John A.
Published: September 2010

The purpose of applying a laser beam in the micro-laser assisted machining (μ-LAM) process is to preferentially heat and thermally soften the surface layer of the work piece material (4H-SiC) at the interface with a diamond cutting tool. In the μ-LAM process the laser beam (1480 nm and 400 mW) is delivered to the work piece material through a transparent diamond cutting tool. Thus the cutting tool and the laser system are integrated and coupled; in contrast with other LAM processes where the cutting tool and laser are separate and distinct systems. Scratches were made on a 4H-SiC substrate using the μ-LAM process. The characteristics of the scratches, such as depth and width, are principally a function of the cutting tool geometry, applied forces, cutting speed, and laser heating. White light interferometer microscopy and Atomic Force Microscopy (AFM) techniques were used to measure the geometry (depth and width) of the scratches. Force analysis was carried out to evaluate the laser heating effect on the cutting forces and the measured depth of cut. The force analysis included an evaluation of the mechanical work, specific energy, and understanding the effect of laser heating on the cutting process. The scratch tests performed on 4H-SiC with the laser heating showed that there is a greater than 50% reduction in relative calculated hardness values of work piece material, resulting in a significant reduction in cutting forces.
Vessel Power Prediction and Its Impact on Emission Inventory
Authors: Wang Fangfang , Bao Han P.
Published: September 2010

Current practice of emission estimate for ocean-going vessels largely relies on the conventional propeller law for determining power consumption. This practice tends to underestimate the actual emission when sea states and winds are ignored. This paper presents an evaluation of two approaches on the prediction of power of a container vessel. The first approach estimates vessel power as a function of the vessel speed according to the propeller law. While the propeller law approach is cost-effective and time-saving in computing vessel propulsion power, it generally under-estimates vessel propulsion power due to the omission of many other influencing factors including vessel course, engine model, ocean states and weather conditions. The second approach derives vessel propulsion power as a function of the vessel speed and resistance forces. The propulsion power required for a particular vessel behavior is determined based on vessel towing resistance, added resistance from waves and winds, and a variety of propeller and hull dependent efficiencies. Because of the incorporation of external factors, this approach should be more accurate than the propeller law in reflecting the actual vessel power requirement. Comparative analysis is conducted among the two estimate results and real measurement data on engine power output. The results clearly show that power estimated from the propeller law underestimate the vessel propulsion power and the gap increases much faster for higher vessel speeds. Power estimate from the second approach provides more accurate results as they greatly match the measured power values. The ups and downs of the prediction results precisely reflect real power variation along with speed changes. Improved power prediction leads to more reliable emission inventory calculation. However, the improvement of accuracy should be balanced with the increased requirement on data sources and computing efforts.
Sustain-A-Bear™: Applying Manufacturing Sustainability Practices to Plush Stuffed Animals
Authors: Laskowski Christina , Snelson Todd , Safir Saadia
Published: September 2010

The stuffed toy market is quite large, with some manufacturers earning nearly half a billion dollars in revenue per year. However, the vast majority of manufacturers do not currently employ sustainable manufacturing techniques. This paper documents the development of a cost-effective stuffed product by placing an emphasis on sustainability within the design process while maintaining the user appeal of a traditional teddy bear. Specifications were determined by analyzing each of the four stages of the product timeline (extraction, manufacture, use, and disposal) to ensure that sustainability was considered throughout the lifecycle of the product. Material choice was a main focus of the extraction stage, and limiting new material usage was an important goal. Considerations for the manufacturing stage included carbon dioxide produced, waste generated, toxicity, and packaging. Specifications regarding the consumer’s use of the product included user appeal, stain resistance, durability, price, and safety concerns. Objectives of the last stage, disposal, included plans to minimize the amount of material sent to landfills by making the product easier to store, improving ease of recycling, and reducing transportation required. These specifications, importance ratings, marginal values, and ideal values are discussed. While investigating more sustainable manufacturing practices, many solutions were found, and the practicality of these solutions was investigated. By incorporating these solutions, the product — Sustain-A-Bear™ — met specifications, embodied sustainability, and also proved cost competitive. Once specification-level analysis was complete, multiple bears were constructed, both to create a baseline for comparison with standard stuffed animal assembly and also to aid in the development of a more sustainable assembly process. Through the use of ultrasonic welding for material bonding to thermally weld materials together and through the use of specialized platens, the bear was assembled from PET fleece (recycled from plastic soda bottles) using significantly less time and energy than that required to sew a bear together. Part reduction and shape simplification also aided bear assembly throughput. Furthermore, tensile testing on an Instron machine yielded results better than those resulting from sewing, owing largely to the reduction of stress concentrations. Finally, overall cost analysis indicates that stuffed animals made in this fashion could, in fact, be affordably made in the United States.
Emerging Trends in Mechatronics and Smart Manufacturing
Authors: Shetty Devdas , Manzione Lou
Published: September 2010

The importance of mechatronics is evidenced by the myriad smart products that we take for granted in our daily lives, from the wall climbing robots to advanced flight control systems and multifunctional precision machines. The multidisciplinary mechatronic field offers optimum solutions to a multivariable problem. The technological advances in digital engineering, simulation and modeling, electromechanical motion devices, power electronics, computers and informatics, MEMS, microprocessors and DSPs have brought new challenges to industry and academia. Modeling, simulation, analysis, virtual prototyping and visualization are critical aspects of developing advanced mechatronic products. Competing in a global market requires the adaptation of modern technology to yield flexible, multifunctional products that are better, cheaper and intelligent. This presentation will examine recent advances of mechatronics in smart manufacturing and will examine (a) Development and implementation of original and innovative mechatronic systems, (b) Additional modifications and improvements to conventional designs by using a mechatronics approach.
A Volume-of-Fluid Based Numerical Simulation of Solidification in Binary Alloys on Fixed Non-Uniform Co-Located Grids
Authors: Farrokhnejad Mehdi , Straatman Anthony G. , Wood Jeffrey T.
Published: September 2010

In this paper, the authors present a platform for the modeling of mold filling and solidification of binary alloys with properties similar to Mg alloys. A volume-of-fluid (VOF) based method is used to capture the interface between solid and liquid in binary alloys solidification process on a fixed non-uniform grid, developed for implementation in a colocated finite volume framework. Contrary to other works, to update the volume fraction (of fluid) in the field, a link between source-based type of energy equation and VOF reconstruction algorithm is described and implemented. A new approximation to the pressure gradient is presented to remove all ‘Spurious Currents’ [1] resulting from pressure jumps in the vicinity of the interface. Based upon the work presented, it is concluded that the present combination of the equations are not only computationally straightforward to implement and upgrade to a 3D problem, but also provides an excellent platform to capture the interface between constituents in a die-casting process including solidification and mold filling process. The current framework will be used in future works to characterize the local mechanical properties of Mg alloys by using information from simulation at the dendritic level.
Measurement of Tool Temperature Using Thermal Imaging in Interrupted Cut Turning
Authors: Smith Scott , Woody Bethany A. , Tursky David A. , Barkman William E.
Published: September 2010

The creation of oscillating tool paths for turning operations that use the numerically controlled machine axes to ensure reliable chip breaking has been demonstrated in a variety of materials. The interrupted cuts created in this way have the additional benefit of allowing the temperature of the tool-chip interface to be controlled at a significantly lower level than in conventional turning. In traditional continuous turning, the interface temperature rises to a high level and stays there during machining. This is especially a problem for difficult-to-machine materials, because many tool wear mechanisms are strongly temperature dependent. In the chip breaking tool paths, the axes of the machine are used to oscillate the tool along the programmed tool path and before the temperature has a chance to rise to damaging levels, the cut can be interrupted so that the tool can cool. This is analogous to the technique of using shallow radial depths of cut in milling operations for difficult-to-machine materials. In this work, a thermal imaging camera is used to verify that this strategy can be effective in the machining of steel. The results from the thermal imaging studies show that over a broad range of conditions, oscillating tools paths create lower temperatures at the tool-chip interface.
AWJ Milling of Gamma Titanium Aluminide
Authors: Hashish Mohamed
Published: September 2010

A study was undertaken to determine the feasibility of the AWJ process for controlled depth milling of gamma Titanium Aluminide tiles. It was demonstrated that milling can be accomplished to 0.025-mm accuracy. To overcome undercutting near rib roots, the jet was clock-angled at about 15 degrees to the vertical every set of passes. This allowed the milling to thin skins of about 0.5-mm. It was observed that as the material is milled, stresses were relieved and either deformation or cracking may result. Accordingly parts need to be annealed before milling. The milling to thin skins was successfully demonstrated on 150mm × 300-mm parts without adverse effects. Also, the process of milling of dual rib height was developed using dual mask approach. Abrasive particle embedding on the milled surfaces was observed to be about 0.15% of the area, but cleaning with plain waterjets showed that all embedded particles can be removed. A detailed economic analysis confirmed that the AWJ milling process is relatively inexpensive and highly productive. The complete cost of milling including mask cutting, overhead, capital, and running cost is less than $300/ft2.
The Laser-Assisted Edge Milling of Ceramic Matrix Composites
Authors: Rozzi Jay C. , Barton Michael D.
Published: September 2010

On this Phase I SBIR project, Creare’s overall objective was to develop and transition a technology that will increase cutting tool life and reduce overall production costs of machining ceramic matrix composite (CMC) materials. We successfully demonstrated the feasibility of machining CMC materials using the Laser-Assisted Machining (LAM) approach, which utilizes a laser to preheat a thin layer of the CMC material prior to its removal using conventional machine tools. In particular, we demonstrated that the cutting forces were reduced by as much as 40% compared to conventional machining processes. This reduction enables increased processing speeds which decrease cycle times and overall processing costs. Additionally, we developed and validated a comprehensive thermal model for the edge machining of CMCs. When combined with the experimental results, the temperatures near the material removal interface for the optimal LAM condition were predicted.
An Efficient One-Step Inverse Approach Based on Nodal Tangent Plane
Authors: Zhou Ping , Hu Ping , Li Guang , Zhang Xiangkui
Published: September 2010

An efficient One-Step inverse approach (IA) based on nodal tangent plane (NTP) is proposed to predict the optimum blank shapes and sizes and reasonable estimation of forming severity (i.e., thickness, strain distributions) from desired final workpieces. According to the deformation theory of plasticity, Hill’s planar isotropic yield criteria and the principle of virtual work (PVW), the non-linear elasto-plastic finite element equilibrium equations are obtained, in which the simplified boundary force conditions are also implemented to simulate the effects of punch, die, blank-holder and draw-bead. For solving the non-linear problem, Newton-Raphson method is used. However, in traditional One-Step IA, the local element stiffness matrix is assembled in the global coordinate system where bad convergence is always a severe problem, especially when vertical or quasi-vertical walls happen. Fortunately, the NTP method provides a smart solution to enhance the convergence, where the ill-conditioned matrix is avoided by assembling the local element stiffness matrix to the tangent plane and to the normal of node. The developed algorithm is integrated into independently developed KMAS (KingMesh Analysis System) for sheet metal forming. To validate its efficiency and feasibility, it is applied to square cup deep drawing of Numisheet’93 and front fender forming of Numisheet’2002 by comparing with DynaForm based on incremental algorithm and traditional One-Step IA.
An Improved Digital Image Correlation Method Applied to Scanning Probe Microscope Images
Authors: Chu Wei , Fu Joseph , Vorburger Theodore
Published: September 2010

Digital image correlation (DIC) is a method for measuring the surface displacements and displacement gradients in materials under deformation. The method has also been applied to the calculation of image distortion for scanning probe microscopy (SPM). The traditional DIC method directly uses the intensity values of compared images but does not take out-of-plane nonlinearity error into account. However, in SPM measurements, the recorded z-direction value is a sum of the real surface height of the sample and any longitudinal deformation of the piezoelectric tube. In order to improve the calculation accuracy of the displacement fields, an improved DIC method is performed here. Two new parameters related to out-of-plane error are introduced in the mathematical modeling. The in-plane displacements between two compared images are then calculated pixel by pixel, with the z-direction error accounted for. This method is tested by applying it to two pairs of atomic force microscopy (AFM) images along the fast and slow scan directions.
Effects of Chip Seizure on Steady State Motion of a Machine-Tool
Authors: Gegg Brandon C. , Suh Steve S.
Published: September 2010

The steady state motion of a machine-tool is numerically predicted with interaction of the chip/tool friction boundary. The chip/tool friction boundary is modeled via a discontinuous systems theory in effort to validate the passage of motion through such a boundary. The mechanical analogy of the machine-tool is shown and the continuous systems of such a model are governed by a linear two degree of freedom set of differential equations. The domains describing the span of the continuous systems are defined such that the discontinuous systems theory can be applied to this machine-tool analogy. Specifically, the numerical prediction of eccentricity amplitude and frequency attribute the chip seizure motion to the onset or route to unstable interrupted cutting.
Modeling of Thermal Dynamics of Dies Using Neural Networks
Authors: Seo Jaho , Khajepour Amir , Huissoon Jan P.
Published: September 2010

The objective of this research is to identify a dynamic model that describes the temperature distribution in a die using a neural network (NN) approach. By using data sets obtained from a finite element analysis (FEA) of the thermal dynamics of a die and applying NN off-line and on-line learning algorithms, the die model is identified. This identification approach has been conducted assuming fully measurable and partially measurable states. For the latter, a NN based adaptive observer is employed to estimate unmeasurable states. It is shown that the complex behavior of the die system with cooling channels can be accurately identified in both cases of fully and partially measurable states.
Blank Design by ANN in Bimetallic Deep Drawing
Authors: Morovati Mamaghani M. R. , Dariani B. M. , Haddadzade M.
Published: September 2010

The present paper deals with the initial blank design of bimetallic parts obtained by deep drawing process. Normally in deep drawing, the initial blank has a simple shape and after drawing, its perimeter shape will become very complex and has considerable influences on the forming results. If the initial blank shape is designed in such a way that is formed into the desired shape after the drawing process, not only it reduces the time of trimming process, but also decreases the drawing force and the raw material needed substantially. The present paper proposes a novel approach to initial blank optimization in multilayer deep drawing. The Finite Element Method (FEM) is employed for simulating multilayer plate deep drawing process to provide training data for Artificial Neural Network (ANN). The aim of the neural network is to predict the initial blank shape for the desired final shape. The FEM results were verified through experiment.
A Unified Simple Predictive Model for High Fluence Ultra-Short Pulsed Laser Ablation of Metal, Semiconductor and Dielectric
Authors: Wu Benxin , Shin Yung C.
Published: September 2010

A unified simple predictive model has been presented for high fluence ultrashort laser ablation of metal, semiconductor and dielectric, which has very low computational cost and is very easy to apply. Unlike many other simplified models, this model does not involve any free adjustable variables. The model predictions agree well with experimental measurements for femtosecond laser ablation, while the model is not very applicable for pulse durations more than ∼10 picosecond.
Parametric Study of Process Parameters and Characterization of Surface Texture Using Rotational-Magnetorheological Abrasive Flow Finishing (R-MRAFF) Process
Authors: Das Manas , Jain V. K. , Ghoshdastidar P. S.
Published: September 2010

In this paper an effort is made towards improving the performance of MRAFF process by providing a rotating magnetic field externally to the polishing medium by using permanent magnets in addition to the reciprocating motion provided to the polishing medium by a hydraulic unit. This finishing process creates a smooth mirror like finished surface with a few directional cutting marks (i.e. hatch pattern like honing) on the finished surface of stainless steel, brass, and EN-8 workpieces. Preliminary experimental study is conducted on MRAFF and rotational (R)-MRAFF processes to compare their process performance in terms of change in Ra (ΔRa) and change in material removal (ΔMR). Later complete experimental study of R-MRAFF process is carried out using central composite rotatable design (CCRD) and the responses are plotted using response surface methodology (RSM). Optimum finishing conditions are identified by optimization method developed by Derringer and Suich using Design-Expert® software. The present study shows that rotational speed of the magnet has significant effect on output response (%ΔRa). The finished surfaces are characterized in detail by atomic force micrographs (AFM), and scanning electron micrographs (SEM) to analyze the changes in surface generation at different RPM.
Effect of Facility Geometry on RFID Localization Accuracy
Authors: Zhou Junyi , Shi Jing
Published: September 2010

Radio frequency identification (RFID) is a promising technology for localization in various industrial applications. In RFID localization, accuracy is the top performance concern, and it is affected by multiple factors. In this paper, we investigate how the facility geometry impacts the expected localization accuracy in the entire region where the target is uniformly distributed. Three groups of geometries, namely, rectangles with various length-to-width ratios, circle, and regular polygons with 3–10 edges, are chosen for this study. A hybrid multilateration approach, which combines linearization and nonlinear optimization, is used to estimate the target location. Since the layout of landmarks significantly affects localization performance, we evaluate the expected accuracy in a facility obtained under the optimal landmark layout for the facility. The optimal landmark layout for each type of facility geometry is obtained, and then the effect of geometry is studied by comparing the expected accuracies of these layouts. It is discovered that (1) the optimal layouts follow several simple empirical deployment principles, (2) for all geometries, the expected accuracy improves and tends to reach the expected Cramer-Rao lower bound as more landmarks are used, and (3) if the same numbers of landmarks are used, the expected accuracies for circular and regular polygonal geometries are close. However, the expected accuracy for a rectangular geometry decreases as the length-to-width ratio increases.
Fabrication of Graded Structures in SiC-Reinforced Metal Matrix by Semisolid Powder Processing
Authors: Wu Yufeng , Kim Gap-Yong , Anderson Iver , Lograsso Thomas
Published: September 2010

Functionally graded structures offer innovative solutions to various challenges in materials engineering. However, the increasing demanding of FGSs has been hindered by the complex processing methods, high cost and composite control difficulties. By combining the concept of semisolid forming and powder metallurgy, semisolid powder processing provides a novel solution to the fabrication of FGS materials. In this paper, a two-layer FGS with one layer reinforced by SiC particles was fabricated with semisolid powder processing. The results indicate that, when the SiC particles are larger than the matrix powder, dense and strong parts can be formed. Smaller SiC particles can isolate the metal powders and resulting in porous and weak structures. Also, the roughness of the SiC particle surface affects interface bonding between SiC particles and Al-Si-Cu matrix phase. In summary, semisolid powder processing is capable of fabricating graded structures with promising microstructures and mechanical properties.
Micro Thin Film Thermal Sensors Embedded Into Polycrystalline Cubic Boron Nitride (PCBN) for Advanced Machining Study
Authors: Werschmoeller Dirk , Li Xiaochun
Published: September 2010

Monitoring and control of thermomechanical parameters in tooling materials are imperative for improving the fundamental understanding, reliability and workpiece quality of material removal processes. Polycrystalline cubic boron nitride (PCBN) tools are being used heavily in machining of low carbon steel and superalloys. These processes are very sensitive to variation in local machining conditions and there lacks a thorough understanding of fundamental thermomechanical phenomena which can lead to abrupt tool failures. Existing sensors for monitoring machining conditions are not suitable for precision process control as they are either destructively embedded and/or do not possess the necessary spatial and temporal resolution to monitor temperature during machining effectively. This paper presents a novel approach to obtain temperature data from a close distance to the tool cutting edge. An array of 9 micro thin film thermocouples, fabricated using standard microfabrication methods, has been embedded into a PCBN cutting tool using a diffusion bonding technique. Scanning electron microscopy (SEM) was performed to examine material interactions at the bonding interface and determine optimal bonding parameters. The sensors were statically and dynamically characterized using a tube furnace and rapid laser heating, respectively. They exhibit good linearity, sensitivity and very fast response time. The instrumented PCBN inserts were applied in machining experiments. Being embedded into the tool at a total distance of only 260 μm from the cutting edge, the micro sensors enabled the detection of local cutting temperature changes caused by interrupted machining. The data obtained during cutting demonstrate the functionality of the tool-embedded micro thermal sensors and their value for fast, accurate and reliable monitoring and control of machining processes.
Hierarchical Coding/Retrieval System of Mechanically Oriented Products
Authors: Adeoye A. O. M. , Sze´csi T.
Published: September 2010

Much attention has been given to parts hierarchical classification, coding and retrieval systems. Much work has been carried out in the retrieval of design images that are similar to the candidate image from the database. However, little has been said or done when it comes to using Group Technology (GT) techniques for the classification, coding and identification of products that are similar by searching through the database using a wide variety of search parameters, especially of mechanically oriented products in a manufacturing environment. This paper presents a method of using the GT to classifying, coding and retrieving of identical or similar products from a database for the purposes of Customer-Led Design, based on the principle of Group Technology classification and coding. The proposed method is based on a hybrid (Chain-Hierarchical type) classification system using a wide range of product parameters. The search and sorting procedure uses the weight factor and similarity index (SI) methods for the identification of similar products. This method generates a list of product codes for the similar products, and ranks the Product Attributes according to their priority vector. The method is successfully implemented in a new Customer-led Design (CLD) environment.
Fabrication and Characterization of Bulk Nanocrystalline Layer in Steel and Aluminum Alloys Formed by Shot Peening
Authors: Waikar R. , Guo Y. B. , Woodbury Keith A.
Published: September 2010

The formation of bulk nanocrystalline (NC) layers in AISI 1075 pearlitic and martensitic steels and aluminum alloys 6061-T6 and 7075 using air blast shot peening was studied. The cross-sectional microstructure of the samples showed a gradual reduction of the grain size near the surface. The NC layers were characterized using optical and scanning electron microscopy and nanohardness measurements. 2D surface topography of the top surface was also carried out. The roughness of the peened surfaces depends on sample hardness. The hardened AISI 1075 martensitic steel had lower surface roughness value. NC layers of 5 to 15 μm thickness were observed in the steels whereas the aluminum alloys 6061 and 7075 yielded NC layers up to 20 to 25 μm thick. The measured nanohardness in the NC layers confirmed the higher hardness of the NC layer compared with the bulk material.
Optimal Scheduling to Achieve Energy Reduction in Automotive Paint Shops
Authors: Wang Junwen , Li Jingshan , Huang Ningjian
Published: September 2010

The largest amount of energy consumption in an automotive assembly plant is in paint shop. Optimizing the energy usage in paint shops will result in maximum energy savings. Instead of inventing new chemicals, new painting processes or new control systems in painting booths and ovens, our research focuses on developing an optimal scheduling procedure of vehicle sequence to achieve the goal of energy reduction. Specifically, by selecting appropriate batch and sequence policies, the paint quality can be improved and repaints can be reduced so that less material and energy will be consumed. It is shown that such scheduling and control method can lead to significant energy savings with no extra investment, nor changes to existing painting processes.
Evaluation of Diagnostic Performance for the Gear Box Considering the Measurement Position Effect With Wavelet Packet Transform
Authors: Hong Young-Sun , Lee Gil-Yong , Cho Young-Man , Ahn Sung-Hoon , Song Chul-Ki
Published: September 2010

There has been much research into monitoring techniques for mechanical systems to ensure stable production levels in modern industries. This is particularly true for the diagnostic monitoring of rotary machinery, because faults in this type of equipment appear frequently and quickly cause severe problems. Such diagnostic methods are often based on the analysis of vibration signals because they are directly related to physical faults. Even though the magnitude of vibration signals depends on the measurement position, the effect of measurement position is generally not considered. This paper describes an investigation of the effect of the measurement position on the fault features in vibration signals. The signals for normal and broken bevel gears were measured at the base, gearbox, and bevel gear, simultaneously, of a machine fault simulator (MFS). These vibration signals were compared to each other and used to estimate the classification efficiency of a diagnostic method using wavelet packet transform. From this experiment, the fault features are more prominently in the vibration signal from the measurement position of the bevel gear than from the base and gearbox. The results of this analysis will assist in selecting the appropriate measurement position in real industrial applications and precision diagnostics.
Flow Uniformity Characterization and Its Application in Extruder Flow Channel Design Optimization
Authors: Yao Minwu , Lee Ching-Chih
Published: September 2010

We are interested in developing a general design optimization loop for extruder flow channel inserts based on 3-D finite element analysis (FEA). A key step of the computational procedure is the automated flow uniformity assessment which requires a quantitative characterization of the flow uniformity at the exit opening. To this end, a non-dimensional flow uniformity parameter is proposed, which is independent of flow rate & geometric dimensions and applicable to any shape of the flow channel cross-section. For a rectangular exit opening, two additional flow uniformity parameters are used to characterize the flow distribution in the two principal directions of the exit cross-section. The proposed flow uniformity parameter was successfully used as the objective function in an automated optimization loop for geometric design of flow channel inserts. The automated optimization loop allowed us to explore the design space in a broad range. Simulation results show that flow balance is consistently improved with the expansion of the design search space. It was also found that the automated optimization loop provides a better optimal solution than those obtained from the manual optimization approach under the same pressure-drop constraint.
Integration of Wireless Sensors and Models for a Smart Machining System
Authors: Jerard Robert B. , Fussell Barry K. , Suprock Chris A. , Cui Yanjun , Nichols Jeffrey , Hassan Raed Z. , Esterling Donald
Published: September 2010

This paper describes recent research progress at the University of New Hampshire in the area of “Smart Machining Systems (SMS)”. Our approach to SMS is to integrate models with wireless embedded sensor data to monitor and improve the machining process. This paper discusses recent progress in low-cost wireless sensor development, model calibration methods, model accuracy, and tool condition monitoring for SMS. We describe a system that can estimate tool wear using the coefficients of a tangential cutting force model. The model coefficients are estimated by online measurement of spindle motor power. We also show the use of a cutting tool embedded with a wireless vibration sensor to detect the onset of chatter in real-time.
Overview of an Adaptive Setup Planning Approach for Job Shop Operations
Authors: Wang Lihui
Published: September 2010

This paper presents an overview of an adaptive setup planning system that considers both the availability and capability of machines on a shop floor. It integrates scheduling functions at setup planning stage, and utilizes a two-step decision-making strategy for generating machine-neutral and machine-specific optimal setup plans. The objective is to enable adaptive setup planning for dynamic machining job shop operations. Particularly, this paper documents basic algorithms and architecture of the setup planning system for dynamically assigned machines. It is then validated through a case study.
Shape Memory Property Alteration of Amorphous NiTi Thin Films Through Aging Heat Treatment
Authors: Satoh Gen , Birnbaum Andrew , Yao Y. Lawrence
Published: September 2010

Thin film shape memory alloys have recently become a promising material for actuation of devices on the micro scale such as micro-pumps and micro-valves. Their utilization, however, has been limited due to the difficulty in tailoring their properties for different applications. Control over the transformation temperatures as well as mechanical and shape memory properties is required to enable their widespread use. This study examines the effects of heat treatment time and temperature on the properties of amorphous, Ti-rich NiTi thin films on silicon substrates. The effects on the transformation temperatures are investigated through the use of temperature dependent optical microscopy. The modulus and hardness, as well as dissipated energy and depth recovery are obtained through nano-indentation and atomic force microscopy (AFM). The role of microstructure and composition in altering both the mechanical and shape memory properties of the films is discussed.