bluuebunny/crossref_metadata_2025 huggingface dataset:
The Thermal Compressive Behavior of a NiTi Fiber 6082-T6 Aluminum Alloy Matrix Composite
Authors: Armstrong William D. , Lorentzen Torben
Published: July 2023

A basic study was conducted of the constitutive response of a 20.5 volume percent, 50.7 at% NiTi shape memory alloy fiber reinforced 6082-T6 aluminum alloy matrix composite (SMA-MMC). The test materials were initially subjected to a 4% tensile prestrain at 19°C. The later stages of the prestrain process resulted in the strong growth of the martensite (001) diffraction peak. During a subsequent 19°C to 120°C unconstrained heating process, the SMA-MMC exhibited a nonlinear thermal contraction, and a strong decrease in the NiTi martensite (001) neutron diffraction intensity. Both experimental effects resulted from a powerful martensite to austenite shape memory transformation in the NiTi reinforcement. The experimental results are analyzed by a nonlinear Eshelby model, which describes the SMA-MMC phase state, external strain, and internal stress during the unconstrained heating process.
Actuator Placement and Selection in Static Deflection Control of Adaptive Structures
Authors: Baerwald Jeff E. , Gerwe Caroline E. , Utku Senol
Published: July 2023

Recently, in many branches of engineering, adaptive structures have received increased attention. An adaptive structure is an intelligent system that uses deformation inducing actuators for its adaptability. The potential uses of such structures stretch beyond civil engineering into the fields of mechanical engineering, aerospace engineering and robotics. With the ability to control in real time some of the critical response quantities, adaptive structures can be constructed more economically than their non-adaptive counterparts which are often over-designed in order to compensate for the large uncertainties in the loads. Although in most of the deflection control problems the number of actuators, q, is at least as great as the number of observed response components, p, the majority of the previous literature has studied actuator placement problems where q < p. The higher level of interest of the q < p case stems from the facts that (i) the difficulty in implementing multi-input multi-output control increases with increasing q, (ii) the cost of actuators increases with q, (iii) the proposed algorithms for this purpose can keep many large computers busy for a long time and end up with a mathematically unverifiable best placement when q is large. In this work, some of the algorithms for the actuator placement problem for controllable adaptive structures are reviewed for q = p and q > p cases, and extensions proposed. When q > p it is shown that the problem of actuator selection arises for economical operation of adaptive structures. The actuator selection problem is also an optimization problem that needs solutions in real-time.
Development of Mesoscale Actuation Device
Authors: Zhu Jinghui , Wang Donny , Kim Chang-Jin , Carman Greg P.
Published: July 2023

We propose to incorporate the micrometer-scale machining capability of Microelectromechanical Systems (MEMS) into millimeter-scale inchworm actuators to achieve large translational force as well as large displacement. The sliding surfaces of the inchworm device is micromachined from silicon wafers, while the PZT actuators are off-the-shelf. Large force becomes possible since the microscopic ridge patterns on the surfaces of inchworm and stator interlock each other as opposed to the smooth surfaces of existing inch-worm devices. Initial results toward the development of Mesoscale Actuation Devices (MAD) is reported in this paper. The fabrication process for the surface with microridges is described. An experimental setup has been developed to visualize and study the engagement and disengagement of a pair of microridged surfaces under the microscope. With further development, continuous inchworm motion by repeated stepping of the microridges is demonstrated. Current status for the development of load-bearing actuators is also discussed.
Photodeformation and Light-Temperature-Piezoelectric Coupling of Optical Actuators: Part 1 — Parameter Calibrations
Authors: Liu B. , Tzou H. S.
Published: July 2023

Conventional hard-wired sensor/actuator systems are sensitive to strong electromagnetic fields. The metallic signal busses act like antennas attracting electric noises. Non-contact optical actuators are driven by high-energy lights which do not require hard-wire connections. These optical actuators can operate in hostile and extreme environments with strong magnetic and/or electric disturbances.

In this study, detailed photostricition, pyroelectricity, thermoelasticity and photodeformation of 2-D optical actuators are analyzed. A servo control system is proposed and its governing system equation is derived. System parameters are calibrated with experimental data. Light intensities, induced strain levels, and the maximal actuation frequencies are investigated (Part–1). Photodeformation and distributed actuation are investigated and compared with the experimental results.

The optical actuators are then used in vibration control of rectangular plates (Part–2). Control effectiveness is evaluated.
New Fabrication Process for Active Micro-Sized Metal/Ceramic Devices
Authors: Ervin James D. , Brei Diann , Van Hoy Charles A. , Mawdsley Jennifer R. , Halloran John W.
Published: July 2023

A novel co-extrusion process was investigated as a means of fabricating active micro-sized metal/ceramic devices with high aspect ratios. This process involves mixing ceramic and metal powders with a thermoplastic and forming elements of a device at a scale many times larger than the final device size. These elements are assembled and co-extruded through a reducing die to achieve the desired size and then co-fired to produce the final micro-device. To evaluate the potential of this process for producing micro-scaled ceramic sensors and actuators, devices of various shapes were assembled, co-extruded, and co-fired using alumina, PZT, and PMN-PT. Features as small as 5 microns were achieved using this process. In addition, a PMN-PT/AgPd composite laminate was co-extruded and co-fired to demonstrate the ability to fabricate micro-devices with electrodes. Results of a shape retention study and metal/ceramic co-fire study are described in this paper.
Realizing Systems With MEMS
Authors: Gabriel Kaigham J. , McMichael James M.
Published: July 2023

As computers increasingly leave fixed locations and appear in the pockets and palms of users, they are getting closer to the physical world, creating new opportunities for perceiving and controlling the physical environment. To exploit these opportunities, computers will need to sense and act as well as compute. Filling this need is the driving force for the development of microelectromechanical systems (MEMS).
Ultrasonic MEMS Device for Fluid Pumping and Mixing
Authors: White Richard M.
Published: July 2023

Silicon-based micromachined devices that were originally made for ultrasonic sensing have been shown to pump and mix both gases and liquids. These devices employ megahertz ultrasonic plate waves, generated in piezoelectric films on a microns-thick membrane, to produce an evanescent disturbance in an adjoining fluid. Because of the high acoustic intensity near the membrane, the nonlinear phenomenon of acoustic streaming can occur, producing a steady force in the direction of propagation of the time-harmonic plate wave. Vorticity near the surface also stirs the fluid. We will present measured and (videotaped) experimental results, and describe some applications of this distributed pump and mixer.
Silicon Bulk Micromachining in Tohoku University
Authors: Minami Kazuyuki , Esashi Masayoshi
Published: July 2023

Micro systems which are small sized but relatively complicated intelligent systems were fabricated based on bulk silicon micromachining. Extremely sensitive sensors with thin beam structure, packaged micromechanical sensors for inertia measurement, microactuators as microvalve and optical scanner and active catheter which moves flexibly like a snake in a blood vessel were developed. Silicon nano-wire growth by electric field evaporation using UHV STM and novel three-dimensional micromachining as deep RIE were developed for the fabrication of the microsystems.
Damage in Unidirectional Graphite/Epoxy Laminates Containing a Circular Hole
Authors: Yang Fan , Chow C. L. , Fang H. Eliot
Published: July 2023

In this paper, a damage mechanics model is described for determining progressive damage process of unidirectional graphite/epoxy composite plates containing a central hole subjected to off-axis uniaxial tension. The inelastic behavior of these composite materials is attributed to the irreversible thermodynamics processes involving energy dissipation and stiffness variation caused by damage initiation and accumulation. The mechanical response of the composites is investigated by using a nonlinear finite element procedure formulated with a set of damage coupled constitutive equations. Separate damage criteria are derived for fiber failure and for matrix or fiber/matrix interaction failure in unidirectional composites. Validation of the damage model is achieved by comparing the numerical prediction and experimental data obtained from Moiré interferometry technique. It has been found that failure of the composite material near the hole region takes the form of an extensive damage zone. The macrocrack initiates at the material point near the hole boundary with high damage value and propagates along the direction of damage zone extension. Preliminary results indicate that the proposed damage model is an effective method of studying progressive failure behavior of unidirectional composite laminates containing a circular hole and can be readily extended to examine the damage response of composite structures.
Fire Emergency Ventilation Analysis of a Transit Station Using Computational Fluid Dynamics
Authors: Kumar Kiran , Abu-Zaid Sameer , Overstreet Jamahl , McCleery Jerry E. , Harris Kenneth J.
Published: July 2023

Computational Fluid Dynamics (CFD) is used in this study to evaluate evacuation and possible egress routes during a fire emergency in the proposed San Bruno station of the Bay Area Rapid Transit (BART) system. Three modes of ventilation, namely natural (no fans), push-pull (fans operating in supply-exhaust mode), and exhaust-exhaust (fans operating in exhaust-exhaust mode) are investigated. The methodology adopted for fire and smoke modeling is explained. The modeled geometry of the station includes its various geometrical features such as mezzanine floor, staircases, and exits. Steady-state simulation results for temperature distribution and velocity field for the three ventilation modes are presented and discussed for various sections of the station.
“Appropriate Equivalent Methodology” for Pressure Relief System PHAs
Authors: Berwanger Patrick C. , Kreder Robert A.
Published: July 2023

This article presents the “Berwanger Method”, a step by step process for designing or analyzing a pressure relief system to meet OSHA 1910.119 Process Safety Information (PSI) and Process Hazard Analysis (PHA) mandates. The author demonstrates that, to ensure safe operation and regulatory compliance, the pressure relief design information management system must be based on an equipment list. The previously common practice of using a relief device list as the basis of “verifying” the design is now recognized as incomplete because this method cannot ensure and document that all equipment is in fact protected.

The author also shows how an electronic relational database can be used to maintain the design information.
Human Factors Engineering in Risk-Based Inspections
Authors: Balkey Joseph P.
Published: July 2023

ASME’s Center for Research and Technology Development has published a number of risk-based inspection “guideline” books all with a standard format. Now they are publishing a risk-based inspections “Handbook” for fossil fuel plants that also follows this standard format. However, because portions of the “Handbook” refer to human error, not only has a Human Factors Engineering “Appendix” been added to expand the subject but the “Appendix” has been designed to follow the standard format in all the other risk-based inspection books. This at first seemed to be unusual because the “Handbook” assesses structural failures and the “Appendix” assesses human failures. However, for the parts in the “Handbook” that directly refer to human error, the parts in the “Appendix” closely match the format in the “Handbook”. For the parts in the “Handbook” that do not refer to human error, new purposes were created for those parts in the “Appendix”.

This paper compares the commonalties and differences between the two formats and lists expected findings where the parts match as well as unexpected findings where the parts in the “Appendix” discuss new applications. In these findings, this paper shows that the risk-based inspection procedure in fossil fuel plants require the human error procedure and the results from the human error procedure feed back into the Risk-based inspection procedure.

This paper’s introduction describes the ASME’s overall risk-based inspection program and how the “Handbook” and “Appendix” fit. Next, in the procedure section, the risk-based inspection procedure for fossil fuel plants is described with highlights of where a human error procedure is required and then the human error procedure is described. In the comparison section, the commonalties and differences between the two procedures are described and expected and unexpected findings are discussed. Finally, the paper concludes that both risk-based inspection and human error procedures need to have better plant-specific data and that the number of opportunities are growing for new applications.
Building Usable Change Documentation
Authors: Plung Daniel L. , Mullins William P.
Published: July 2023

Across the missions of the Department of Energy (DOE) the planning of work and the management of risk is a systems problem of exceptional complexity. The shift in the international balance of power at the beginning of this decade dramatically changed the parameters of risk within which the DOE operates. Just a few years earlier federal and state regulatory authority were extended to the waste and environmental aspects of the nuclear weapons complex operations. For many, this also introduced an abrupt change to the historic perception of the risks of these operations. DOE, in the Energy and Research sectors, faces changes in risk management practices as these activities, still governed by DOE’s self-regulation authority in occupational and nuclear safety, are more and more compared to private sector counterparts for cost and safety performance. DOE intends to establish a contemporary, standards-based, integrated safety management system. However, the development of guidance for simultaneous accomplishment of both global and local changes in past practices is far from risk-free. The work of Department Standards Committee provides insight to change management challenges and opportunities on a department-wide scale. The Work Smart Standards protocol developed by the Committee promotes a focus on understanding the actual work/hazards matrix as seen from the perspective of multi-disciplinary teams with concise and relevant experience of that specific work. It also draws attention to the essential role that agreements play in achieving closure on planning and the implementation of plans in the face of persistent uncertainty from a wide variety of sources.
Providing Support That Helps Change Endure
Authors: Butler Ralph A. , Badie Eileen D. , Roberson Dana S.
Published: July 2023

One of the many challenges faced by the Department Standards Committee (DSC) is the support of change. The DSC’s charter is to define departmental criteria for establishing a standards-based management program and to assist in institutionalizing that program in the Department of Energy. Extensive use of the DSC Web Site, which resides on the Internet and is accessible at http://www.dsc.doe.gov/, allows communication of vital information necessary for facilitating and supporting change among many diverse audiences. Through this medium, real-time communication and document transfer can occur. Utilization of Web Site forums allows the interactive conversations necessary for document development, assessment, and concurrence. Interactive assistance by the Web Site Support Team provides on-line help for hesitant users and simplifies document usage and downloading. The DSC Web Site Support Team provides a web site that is simple and effective for users to share ideas and information. By so doing, information on the site is not only available twenty-four hours a day, but organization actions are more easily generated and preserved.
A New Twist to Learning
Authors: Balkey Joseph P.
Published: July 2023

ASME’s Center for Research and Technology Development is publishing a Handbook with a Human Factors Engineering Appendix for risk-based inspections of fossil fuel Plants. This paper shows the results of applying human error and long term memory models to a technique that estimates the optimum time to inspect equipment. One result is clarification of Bayes Rule and the optimum inspection technique. Another result is applying the inspection technique to retraining people. The third result is changing the method of presenting training material.

Table 1 shows how the information in this paper is presented. After a brief introduction, the idea of prior, new information, and posterior is applied to three situations: putting a golf ball, Bayes Rule, and optimizing inspections. The technique for optimizing inspections is then applied to retraining people. Finally, the idea of prior, new information, and posterior is applied as a training method.

This paper has these three goals. One, explain a technique that shows the optimum time to inspect equipment. Two, expand this technique to also show the optimum time to retrain people and a new technique to help retrain them. Three, recognize the need for collecting and maintaining failure rate data.
Nuclear Power Reactor Safety Improvements: Mitigation Versus Emergency Preparedness
Authors: Margulies T.
Published: July 2023

This paper presents a national perspective of the values and impacts of filtered vented containments and instrumentation and monitoring of Event V scenarios as a means to mitigate severe reactor accident releases of radioactivity for operating reactors. The costs are comparable to emergency preparedness measures such as stockpiling potassium iodide for the population and have additional protection benefits of reducing substantially non-inhalation pathway contributions to offsite health effects, as well as, protecting land from contamination.
A Mechanical Reliability Evaluation of Several Electrically Conductive Epoxies: Part II — Thermal Stability and Thermo-Mechanical Creep
Authors: Rafanelli Anthony J.
Published: July 2023

Electrically conductive epoxies have become attractive alternatives to traditional tin-lead solder as bonding media for electronic interconnections. However, these materials, being of a different nature than solder, have not undergone as extensive material and mechanical characterization as the latter. Subsequently, a comprehensive, multi-phase evaluation is warranted prior to approving a direct substitution. Such an evaluation would include several key mechanical studies such as basic material properties, fatigue, creep, and fracture. This paper reports on results of both thermal and thermo-mechanical creep studies performed on samples of conductive adhesive epoxies. In addition, testing was also performed on eutectic or near eutectic solder, to provide a benchmark for comparison. Results on remaining phases will be reported as subsequent parts to this paper.
Control of Thermal Deformations of Integrated Optical and Shape Memory Alloys Fibers
Authors: Birman Victor
Published: July 2023

The purpose of this paper is to illustrate one of the possible areas of application of smart materials to microelectronics. The problem considered in the paper is related to the requirement to prevent optical fibers from a contraction at low temperatures. This task is achieved by combining an optical and a shape memory alloy fibers. If the latter is in the austenite phase at a reference temperature, it will experience a martensite transformation when the temperature is reduced below the martensite start value. The martensite transformation of a shape memory material is accompanied by its expansion. Therefore, it is possible to design an assembly where a contraction of the optical fiber will be compensated by an expansion of the shape memory fiber yielding a prescribed deformation.
Physics of Failure Based CAD Software for Reliability Assessment of Hybrid Optoelectronic Packages
Authors: Mead Patricia F. , McCluskey Patrick , Chen Qing Yan , Haislett Don
Published: July 2023

Reliability assessment of microelectronic printed circuit board assemblies has been routinely achieved using physics of failure based CAD software packages that feature closed-form mathematical models for relevant degradation and failure processes. With the current trend toward development of hybrid electronic products that feature optoelectronic components along side microelectronic circuitry, reliability assessment techniques that build upon previously established CAD methodologies are attractive. Development of failure models for optoelectronic components is currently hampered due to the relative immaturity of the optoelectronic market. This has limited useful field data which can help to identify areas of priority, and also provide data leading to physics of failure degradation models. However, incorporation of optical components into CAD reliability software using currently available models is achievable today. This paper reports a CAD reliability assessment of a laser transmitter module which features a fiber pigtailed diode laser bonded to a printed circuit board assembly containing the laser driver and logic circuitry. The assessment has been carried out using existing CAD software developed at the University of Maryland Computer Aided Life Cycle Engineering (CALCE) Electronics Packaging Research Center. A brief review of the CAD resuit is followed by an overview of major failure mechanisms for diode lasers (LDs), light emitting diodes (LEDs) and a few comments on optical fiber interconnect reliability issues. This approach for implementing virtual product verification through CAD assessment of optoelectronic product reliability is suggested, and is particularly useful for product designers and engineers responsible for reliability engineering of hybrid microelectronic/optoelectronic products.
Procedure for CAD Assessment of Thermal Management Performance in a Diode Laser Structure
Authors: Kamath Rajesh R. , Mead Patricia F.
Published: July 2023

This paper outlines a procedure which may be used to formulate a mathematical expression useful for determining thermal management requirements in a semiconductor diode laser structure. A semi-analytical expression is derived for the steady state operating temperature of the laser emitter for a laser array structure. The methodology combines a finite element analysis (FEA) of thermal profiles in a laser structure, a design of experiments (DOE) investigation of various parameters involved in the heat generation and dissipation process, and a theoretical heat transfer analysis of the structure under operation. The FEA output produces a 2-dimensional transient and steady state temperature profile within the laser structure. The FEA method is then used in performing a DOE investigation to determine the thermal effect of specified operating parameters, including laser emitter spacing, laser performance requirements (output power), and heatsink material. Physical relationships derived from heat transfer analysis of the laser structure are used to determine the subset of heatsink material characteristics necessary to produce a valid expression for steady state operating temperature in the laser emitter region as a function of our design variables. Results of the analysis are applied to diode laser degradation mechanisms and the thermal enhancement factors for each mechanism are calculated. This procedure may be used to assess different thermal management strategies and their implications on reliability.
Hybrid Approach to Development of a Separable Interconnection for High Density Applications
Authors: Pryputniewicz Dariusz R. , Pryputniewicz Ryszard J.
Published: July 2023

Competitive trends to miniaturize digital electronic systems have introduced extraordinary challenges concerning the design of the system packages, especially high density packages. This, in turn, has led designers to develop a number of different electrical transmission structures for device interconnections, with particular emphasis on separable interconnections. Development of interconnections employs some of the most advanced technologies available today. These technologies, classified as Analytical, Computational, and Experimental Solutions, constitute ACES methodology, on which a hybrid approach to development of electronic interconnections is based. In this paper, fundamentals of the ACES methodology are briefly discussed, principles of the hybrid approach are outlined, use of this approach to development of a concept of a separable interconnection for high density, high digital speed applications is illustrated, and characteristics of the concept solution are enumerated.
Electromagnetic (EM) Quantification of the Microwave Antenna for the Transurethral Prostatic Thermotherapy
Authors: Zhu Liang , Xu Lisa X. , Yuan David Y. , Rudie Eric N.
Published: July 2023

Experiments were performed in a tissue microwave equivalent phantom gel to quantitatively examine the volumetric heating produced by a microwave antenna with a peripheral cooling system for the transurethral prostatic thermotherapy. The volumetric heat strength. which is determined by the specific absorption rate (SAR) of microwave energy in the gel, was calculated from the initial transient temperatures at various locations within the phantom gel. Based on previous research. expression for the SAR distribution was extended to three dimensions. which includes its dependence on radial, angular and axial direction. The parameters in this expression and the convection coefficient due to the chilled water running around the antenna were determined using a least-square residual fit of the analytical predictions to the experimental SAR measurements. The analytical expression of the three-dimensional SAR distribution obtained in this study will help provide a better understanding of the microwave heating pattern in the prostatic tissue and thus to aid in designing improved applicators. It can also be used in the future as an accurate input to heat transfer models to predict temperature distributions during the transurethral microwave thermotherapy.
Thermally-Induced Pore Formation in Cell Membranes
Authors: Karlsson Jens O. M. , Toner Mehmet
Published: July 2023

A statistical mechanical model of pore formation in lipid bilayer membranes due to thermal fluctuations is coupled with a model of diffusion in pores to obtain predictions of cell membrane permeabilities to a variety of molecules. Predictions of pore size distributions in the cell membrane, as well as activation energies for transmembrane transport, are obtained for water, glycerol, and electrolytes, in a wide range of cell types. A good correlation between theoretical predictions and experimental data from the literature indicates that diffusion through transient bilayer pores may be an important cause of increased membrane permeability in thermally stressed cells.
Measurement of Water Transport During Freezing Using Differential Scanning Calorimetry
Authors: Devireddy Ramachandra V. , Raha Debopam , Bischof John C.
Published: July 2023

A new technique using Differential Scanning Calorimeter (DSC) was developed to investigate water transport in whole tissue slices (1–5 mm3) and suspended cells during freezing. The tissue and cellular DSC data were correlated to water transport data by freeze substitution tissue microscopy and standard cellular cryomicroscopy techniques respectively. Sprague Dawley liver tissue and a (non-attached) lymphocyte (Epstein Bar Virus Transformed, EBVT) human cell system, were chosen as our tissue and cell model systems. The DSC was used to quantitatively monitor the heat released by water transported from the cell to the frozen vascular/ extracellular space in both systems at 5°C/min. Cryomicroscopy experiments verified that at a slow cooling rate of 5°C/min no intracellular ice formation (IIF) occurred in either system. The sub-zero volumes of the tissue and cells were obtained as a function of temperature by both DSC and cryomicroscopy. By fitting a model of water transport for cells and tissues, dV/dt = f (Vb, B, T (t), Lp (Lpg, ELp)), to the DSC data for both systems, the following biophysical parameters were obtained, for rat liver tissue: Lpg = 2.25 μm/min-atm, ELp = 75.76 kcal/mole, and for EBVT lymphocytes: Lpg = 0.15 μm/min-atm, ELp = 28.78 kcal/mole. These results compare favorably to a recent study which found water transport parameters in whole liver tissue (Pazhayannur and Bischof, 1996) and to the single cell cryomicroscopy data we obtained in this study. The DSC technique is shown to be a fast and powerful method to obtain dynamic water transport information during cell and tissue freezing.
Pore Formation and Pore Dynamics in Bilayer Membranes
Authors: Zhelev Doncho V. , Needham David
Published: July 2023

Pore formation in cell membranes is widely used to deliver hydrophilic substances to the cell interior, such as DNA, drugs etc. Among the methods used for pore formation are electroporation and exposure of the membrane to mild surfactants, such as digitonin or lysolipid. Pore formation in the first case is a result of the apparent electrocompression generated across the membrane, while in the second case, it is a result of the preferential partitioning of the surfactant molecules at the edge of spontaneously formed membrane defects. Both in electroporation and when surfactants are used, pores form mainly in lipid membrane domains. Thus, the use of model membranes allows us to access important characteristics of pore formation and dynamics, such as their dependence on membrane composition and far field membrane tension. The role of these characteristics in pore formation is studied by using single lipid vesicles, which are manipulated by glass micropipets.
Thermal Characteristics of Two Phase Thermosyphon Cooling Module for Multi-Chip Device
Authors: Choi Sung-Bong , Nam Sang-Sig , Kim Jae-Hee , Kwak Ho-Young
Published: July 2023

A thermosyphonic cooling module (TSCM) has been designed, fabricated and tested to cool the multi-chip plugged into a planar packaging system. The cooling module consists of a cold plate and an integrated condenser. With an allowable temperature rise of 56 °C on the surface of the heater, the cooling module TSCM can handle a heat flux about 2.7 W/cm2.

The transient characteristics of the cooling module have proved to be excellent; that is, when a heat load is applied to the system, steady state can be achieved within 10 ∼ 15 minutes. It has been found that the length of the vapor channel between the cold plate and the condenser and ambient as well as the condenser temperatures affect the system performance.
Lean Manufacturing Cell Design
Authors: Black J. T.
Published: July 2023

In the lean production company, the manufacturing engineers are responsible for designing, building, testing, and implementing the manufacturing equipment for the manufacturing cells. These cells are designed for flexibility — they can handle changes in product design as well as external customer demand. This means the manufacturing engineer must have machine design skills in addition to system design skills. The key here is that the manufacturing equipment is custom designed and custom built for the manufacturing system and for the users of the equipment (the internal customer). However, many companies have designed interim cells using machine tools designed for stand-alone applications in the job shop. Industrial examples of these two kinds of cells are presented.
Automated Customized Fixture Configuration Design for Rapid Response Manufacturing
Authors: Wu Y. , Rong Y. , Chu T. C.
Published: July 2023

Flexible fixturing is a necessary aspect of FMS and CIMS. Computer-aided fixture design (CAFD) has become a research focus in implementing FMS and CIMS. Although modular fixtures have been used in industry as flexible fixtures, there are some limitations to be used in large-batch and mass productions where dedicated fixtures are utilized. By combining CAFD with 3-D lithographic and/or CNC machining techniques, customized fixtures can be rapidly designed and fabricated to reduce manufacturing lead-time.

In this paper, an automated customized fixture design system is introduced. Based on fixture structure analysis. fixtures are divided into functional components, fixture bases, and supporters of connections. A geometry-element generator is designed to adaptively generate fixture components with dimensions according to workpiece geometry and operational information. Locator/clamp selection is automatically conducted with connections to a fixture base. Once fixture units are designed individually. the connections may be modified into combined units based on certain criteria. Interference checking and fixture unit modifications are also automatically performed in the system. Fixture design examples arc given at the end of the paper.
A Dynamic Feedback Method for Machine Selection: Prototype and Simulation Study for Integrated Process Planning
Authors: Zhang Daguang , Zhang Hong C. , Smith M.
Published: July 2023

Process planning is usually performed without concurrent considerations on production constraints, and hence the resultant plans are less valid in terms of schedulibility. Among several attempts to create integrated algorithms for process planning and scheduling, very little has been done successfully in developing an integration prototype under which the related integration algorithms can be justified. This paper first briefly reviews the background of this dynamic multi-objective decision problem. Then a prototype is proposed with a heuristic integrative algorithm — machine selection using a dynamic decision table which is maintained by dynamic loading feedback method. A simulation study was performed to verify the algorithm and the significant outcomes were obtained.
The Strengthening and Dragging Characteristics of Dilute Sn Solders Designed for Electronic Packages
Authors: Guo Zhenfeng , Gher Thomas J. , Sarafids Cynthia T. , Lucey George K.
Published: July 2023

The monotonic plastic flow behavior and deformation kinetics of solder joints in shear at room temperature were determined for some dozen dilute Sn solders designed for Pb-free alternatives in electronic packages. In, Bi, Ag and Cu elements were involved in alloys based on Sn. The Bi solute atoms (s.a) in the Sn host lattice were found to be a significant species in solid solution strengthening and the In s.a. a significant species in impeding recovery. The Bi solute strengthening process was in accord with Labusch’s statistical model (Labusch, 1970). The model relation otherwise predicted a Bi and In interaction strengthening. The rate-controlling mechanisms in recovery were speculated to be an In-solute-viscous-dragging and glide-controlled creep and a Bi-solute-dragging and climb-controlled creep in the corresponding alloys. The actions of electron concentration (e/a) were noted.
An Introduction to Predict the Fatigue Lifetime and Strengthening Directions of Solder Joint in Electronic Packages
Authors: Guo Zhenfeng
Published: July 2023

An overview was given to Coffin-Manson (C-M) methodology, fracture mechanics technology, and their applications to the fatigue lifetime prediction of solder joints in electronic packages, and their limitations were analyzed as well. An empirical relation of fatigue cracked area growth rate vs hysteresis energy rate was introduced to predict the fatigue lifetime and the strengthening directions of solder joints. To predict the strengthening directions was to predict the failure mechanisms. The predicted fatigue failure rate-controlled factors tell us that the TMF failure of Pb-Sn solder joints is determined by Sn matrix fracture capacity associated with subgrain structure and persistent slip bands. The Pb-phase fracture capacity is smaller as indicated by the propensity of Pb-phase cracking at me intermediate temperatures. The fatigue cracking resistance of the grain and interphase boundaries is high at higher temperatures and larger strain ranges. A fatigue lifetime prediction system was in perspective.
Significance of Quill Motion for Efficiency and Accuracy in Jig Grinding With Electro-Deposit CBN Wheel
Authors: Matsuo T. , Sakamoto H. , Touge M.
Published: July 2023

Jig grinding is well known as a precision internal machining process for high precision products such as dies and fixtures. Jig grinders are usually used for grinding holes and various contour holes to accurate size and location. In this research, an investigation to realize high productivity and high accuracy in Jig grinding was performed on a hardened die steel with electro-deposit CBN grinding wheels under different grinding conditions. In special, the effects of quill motion and wheel speed on grinding characteristics have been clarified. Grinding forces (Ft, Fn), surface roughness, and accuracy (roundness) were measured, and also the machining mechanism in Jig grinding was discussed from the result of SEM observations. A clear reduction of grinding forces was found by an application of quill motion, and also better surface finish was obtained. The reason for this is related with the fracture of the grain corners. Increasing wheel speed was also very effective for decreasing grinding force and roughness.
Surface Analysis of Zirconia-Toughened Alumina Lapped With Polycrystalline Diamond Powders
Authors: Marinescu Ioan D. , Turco Marc D.
Published: July 2023

Flat lapping of zirconia-toughened alumina with diamond powders was performed to investigate the influence of contact pressure and abrasive size on the surface profile. Scanning electron microscopy, profilometry and interferometry were used to analyze the surface finish and surface profiles obtained. The wear mechanisms that occur are discussed and related to the surface finish and profiles produced. Results showed that the amount and action of deformation-controlled and micro-fracture controlled wear differ with respect to contact pressure and abrasive size. Interactions occur differently between wear mechanisms resulting in optimum loads or contact pressures with respect to surface finish within the parameters used for this research. The interaction between wear mechanisms can also result in producing surfaces that are similar in finish but have different profiles.
Thermal Simulation and Model-Based Adaptive Control of Plasma-Arc Processing on Metal Plates
Authors: Doumanidis Charalabos C. , Fourligkas Nikolaos
Published: July 2023

This article addresses real-time control of the temperature distribution in a wide class of thermal processing operations on metal plates. A generic plasma-arc experimental workstation and a flexible numerical simulation of the heat flow is developed for this purpose. However, the inherent nonlinearity of heat transfer mechanisms and the limitations of infrared thermal sensing lead to the establishment of a linearized multiple-input, multiple-output model, with in-process identification of its parameters. This real-time thermal model serves in a Smith-predictor scheme as a reference to the adaptive controller. The thermal regulation system adjusts the power and guides the motion of the torch to the part region with the largest deviation from a desired temperature distribution, using an in-process thermal optimization method based on a moving complex pattern. Besides off-line validation of the models, the closed-loop thermal control strategy is tested both in simulation and in the laboratory on elementary metal processing related to thermal rapid prototyping applications.
Finite Element Analysis of Electromagnetic Forming of Tubes With Fittings
Authors: Mahanian Saba , Blackwell David B.
Published: July 2023

Thousands of feet of tubing are used in building a complex vehicle like an airplane and therefore, it is imperative to have an efficient process to form and connect various tubes together. Electromagnetic expansion forming is a high energy rate forming process which uses an electrical coil inside a tube to produce high pressures (10,000 to 30,000 psi) in short time period (about 20 micro seconds). The pressures are used to expand the aluminum tube against a metal die, in this case another aluminum fitting. The explicit, nonlinear, finite element program, DYNA2D was used to make an axisymmetric model of this forming process. The process involves considerable geometrical as well as material nonlinearity. The effects of the geometrical parameters of the fitting, such as the number of grooves, their depths and their widths, were studied. The effects of process parameters, such as the magnitude and shape of the pressure pulse, were also studied. To test the performance of the forming process, the tubes were subjected to axial loads in order to determine the force it takes to pull the tube out of the fitting. Finite element analysis was performed to simulate this removal process as well. The finite element analysis of the electromagnetic forming process was a key factor in shortening the process design cycle by drastically reducing the number of trial and errors and preventing premature electromagnetic coil failures.
On the Role of Interstand Tension in the Chatter of Rolling Mills
Authors: Cherukuri H. P. , Johnson R. E.
Published: July 2023

Asymptotic methods are used to study the role of interstand tension in the chatter of rolling mills. A two-stand mill is considered and the effect of interstand tension on the vibrations of the second stand is considered. The interstand tension is also the exit tension in the sheet at the exit point of the first stand and therefore, is determined by the rolling parameters of the first stand. The steady part of the interstand tension is shown to cause the effective spring coefficient of the second stand to be very small under some operating conditions. The dynamic part is shown to act as a forcing function to the vibrations of the second mill. The conditions under which interstand tension leads to self-excited vibrations and resonance in the second stand are extracted from the model.
Simulation and Optimization of Assembly Processes Involving Flexible Parts
Authors: Hsieh Ching C. , Oh Kong Ping
Published: July 2023

A method is described for the simulation and optimization of assembly processes involving flexible parts. The method, which can be applied to a wide range of assembly problems, combines traditional elastostatic structural analysis with techniques used to evaluate statistics of system with stochastic parameters. Results from an illustrative sample problem demonstrate the potential of this method in controlling the dimensional variation of the finished product.
Manipulating Machining Temperature for Chip Breaking Improvement
Authors: Hong Shane Y. , Ding Y.
Published: July 2023

Low carbon steel AISI 1008 is known to be difficult for chip breaking in conventional machining. This paper presents an environmentally safe cryogenic machining approach to improve the material properties for easy chip breaking. The ductile-brittle transition temperature for AISI 1008 was experimentally determined to be between −50°C and −120°C. To achieve this temperature in chips, liquid nitrogen was selectively injected to the chip forming area in the cutting process. Finite element analysis was used to predict the temperature distribution under various cutting conditions. Accordingly, the liquid nitrogen spray pattern was fine-tuned so the chip would reach the ductile-brittle transition temperature at chip breaking area. This approach minimizes the consumption of liquid nitrogen, making the process economical and practical. It also avoids the negative effect of increasing the cutting force due to hardness and shear strength increase of the workpiece material at cryogenic temperatures. Cutting tests performed on a CNC turning center showed significant improvement of chip breakability for a given range of feeds and speeds.
Dimensional Measurement Data Analysis: Part I — A Zone Fitting Algorithm
Authors: Choi Woncheol , Kurfess Thomas R.
Published: July 2023

Measured data taken from Coordinate Measuring Machines are Cartesian coordinates of points from the surface of a geometric solid. These points need to be placed in the same coordinate reference frame as the design model to yield deviations from target (design) geometry. Currently, data fitting techniques such as least squares fit or min-max fit are employed to the localize the measured points with respect to the design model. Tolerance verification is accomplished by determining whether the deviations of the measured points are within tolerance limits. If the tolerance is represented by tolerance zones, such data fitting techniques may not fulfill the desired verification objective.

This paper describes a zone fitting algorithm that determines whether a set of points fits into a given tolerance zone. If the point set fits into the zone, it returns a rigid body transformation that places the points inside the zone. If the criterion of a pass/fail decision is to verify whether the measured points fit into the tolerance zone, an approach employing the proposed zone fit yields a more accurate verification result than least squares or min-max approaches as shown in a number of examples in this paper. A subsequent paper (part II) addresses the determination of a minimum zone that extends inspection from a pass fail mode to a quality analysis operation.
Propagating Topological Tolerances for Rapid Prototyping
Authors: Peters T. J. , Demurjian S. A. , Needham D. M. , Peters R. J. , Dorney S. M.
Published: July 2023

Rapid prototyping technologies permit timely inclusion of experimental verification within an iterative design process. This work introduces topological tolerances as a tool for retaining desired design invariance during the production of successively refined prototypes. These topological tolerances are applied to the supporting geometric data representations for rapid prototyping.

At each successive local modification of the geometric data, these topological tolerances must be dynamically updated. These updates are modeled by object-oriented propagations, leading to investigation of efficient algorithms to re-compute these local topological tolerances. Relevant industrial examples will be discussed.

Software to compute topological tolerances has been fully implemented and tested, and one purpose of this paper is to report that development. Another emphasis of this paper is to report upon software prototyping of performance enhancements to adapt this code to support iterative re-design within a rapid prototyping environment. The final emphasis is to report upon our use of object-oriented propagations within our software engineering environment ADAM to model appropriate change notification upon a decision to alter the supporting geometry data structures for rapid prototyping.