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Articles 331 - 360 of 467
Full-Text Articles in Mechanical Engineering
Test 1903: Agco Lt 100a Powrmaxx Diesel, Nebraska Tractor Test Lab
Test 1903: Agco Lt 100a Powrmaxx Diesel, Nebraska Tractor Test Lab
Nebraska Tractor Tests
ABOUT THE TEST REPORT AND USE OF THE DATA
The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.
EXPLANATION OF THE TEST PROCEDURES
Purpose
The purpose of …
Test 1905: John Deere 5603 Diesel 12-Speed, Nebraska Tractor Test Lab
Test 1905: John Deere 5603 Diesel 12-Speed, Nebraska Tractor Test Lab
Nebraska Tractor Tests
ABOUT THE TEST REPORT AND USE OF THE DATA
The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.
EXPLANATION OF THE TEST PROCEDURES
Purpose
The purpose of …
Test 1904: Agco Rt 120a Powrmaxx Diesel, Nebraska Tractor Test Lab
Test 1904: Agco Rt 120a Powrmaxx Diesel, Nebraska Tractor Test Lab
Nebraska Tractor Tests
ABOUT THE TEST REPORT AND USE OF THE DATA
The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.
EXPLANATION OF THE TEST PROCEDURES
Purpose
The purpose of …
Test 1906: John Deere 5625 Diesel 9-Speed, Nebraska Tractor Test Lab
Test 1906: John Deere 5625 Diesel 9-Speed, Nebraska Tractor Test Lab
Nebraska Tractor Tests
ABOUT THE TEST REPORT AND USE OF THE DATA
The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.
EXPLANATION OF THE TEST PROCEDURES
Purpose
The purpose of …
Test 1910: Case-Ih Steiger 480 And Stx 480 Diesel 16-Speed, Nebraska Tractor Test Lab
Test 1910: Case-Ih Steiger 480 And Stx 480 Diesel 16-Speed, Nebraska Tractor Test Lab
Nebraska Tractor Tests
ABOUT THE TEST REPORT AND USE OF THE DATA
The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.
EXPLANATION OF THE TEST PROCEDURES
Purpose
The purpose of …
Test 1911: Case-Ih Steiger 530 And 535 Quadtrac Diesel 16-Speed Also Case-Ih Stx 530 Quadtrac Diesel 16-Speed, Nebraska Tractor Test Lab
Test 1911: Case-Ih Steiger 530 And 535 Quadtrac Diesel 16-Speed Also Case-Ih Stx 530 Quadtrac Diesel 16-Speed, Nebraska Tractor Test Lab
Nebraska Tractor Tests
ABOUT THE TEST REPORT AND USE OF THE DATA
The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.
EXPLANATION OF THE TEST PROCEDURES
Purpose
The purpose of …
Test 1916: Case-Ih Magnum 275 Diesel 19-Speed (Chassis S/N Z7rz05000 And Higher), Nebraska Tractor Test Lab
Test 1916: Case-Ih Magnum 275 Diesel 19-Speed (Chassis S/N Z7rz05000 And Higher), Nebraska Tractor Test Lab
Nebraska Tractor Tests
ABOUT THE TEST REPORT AND USE OF THE DATA
The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.
EXPLANATION OF THE TEST PROCEDURES
Purpose
The purpose of …
Test 1915: New Holland Tg305 And T8040 Diesel 19-Speed, Nebraska Tractor Test Lab
Test 1915: New Holland Tg305 And T8040 Diesel 19-Speed, Nebraska Tractor Test Lab
Nebraska Tractor Tests
ABOUT THE TEST REPORT AND USE OF THE DATA
The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.
EXPLANATION OF THE TEST PROCEDURES
Purpose
The purpose of …
Test 1908a: New Holland Tj380 And T9030 Diesel 16-Speed, Nebraska Tractor Test Lab
Test 1908a: New Holland Tj380 And T9030 Diesel 16-Speed, Nebraska Tractor Test Lab
Nebraska Tractor Tests
ABOUT THE TEST REPORT AND USE OF THE DATA
The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.
EXPLANATION OF THE TEST PROCEDURES
Purpose
The purpose of …
Test 1910a: New Holland Tj480 Diesel 16-Speed, Nebraska Tractor Test Lab
Test 1910a: New Holland Tj480 Diesel 16-Speed, Nebraska Tractor Test Lab
Nebraska Tractor Tests
ABOUT THE TEST REPORT AND USE OF THE DATA
The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.
EXPLANATION OF THE TEST PROCEDURES
Purpose
The purpose of …
Test 1897: John Deere 7930 Ivt Diesel, Nebraska Tractor Test Lab
Test 1897: John Deere 7930 Ivt Diesel, Nebraska Tractor Test Lab
Nebraska Tractor Tests
ABOUT THE TEST REPORT AND USE OF THE DATA
The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.
EXPLANATION OF THE TEST PROCEDURES
Purpose
The purpose of …
Compressor Valve Failure Detection And Prognostics, Raghuram Puthali Ramesh
Compressor Valve Failure Detection And Prognostics, Raghuram Puthali Ramesh
Masters Theses
"Reciprocating compressors are commonly used machinery for industrial applications. Unscheduled downtime and maintenance activity on the compressors causes considerable loss in throughput and efficiency of a plant. Of all the failures that cause unscheduled downtime in reciprocating compressors, valve related causes are predominant. Most of the failures associated with the valves are tracked to the failure of moving elements within the valve. Achieving higher reliability of critical reciprocating systems requires continuously monitoring the system and performing dynamic analysis of the sensory data for valve fault diagnosis. Continuous monitoring will improve the time and cost to repair through keeping a constant …
Adhesion-Delamination Mechanics Of Linear And Axisymmetric Film At Film-Substrate Interface, Ming-Fung Wong
Adhesion-Delamination Mechanics Of Linear And Axisymmetric Film At Film-Substrate Interface, Ming-Fung Wong
Masters Theses
"This thesis is to characterize the thin membrane adhesion-delamination phenomena which occur in biological cells and micro-electro-mechanical systems (MEMS) operation. The delamination of a thin film adhered to a rigid substrate is subjected to the coupling effects of tensile residual stress and interfacial adhesion energy. The adhesion-delamination mechanics is derived using the classical linear elasticity and thermodynamics energy balance. The membrane deformation is here dominated by a mixed plate-bending and membrane-stretching, while the concomitant stress is neglected. An 1-dimensional model is first investigated where a pre-stressed rectangular film clamped at both ends delaminates from a rigid punch of the same …
Empirical Dynamic Modeling And Nonlinear Force Control Of Friction Stir Welding, Xin Zhao
Empirical Dynamic Modeling And Nonlinear Force Control Of Friction Stir Welding, Xin Zhao
Masters Theses
"Current Friction Stir Welding (FSW) process models are mainly concerned with the detailed analysis of material flow, heat generation, etc. and therefore, are computationally intensive. Dynamic models describing the total forces acting on the tool throughout the entire welding process are required for the design of feedback control strategies and improved process planning and analysis. In this thesis, empirical models relating the process parameters (i.e., plunge depth, travel speed, and rotation speed) to the process variables (i.e., axial, path, and normal forces) are developed to describe their dynamic relationships"--Abstract, page iv.
Manufacturing Of High Performance Composites Using Vacuum Assisted Resin Transfer Molding, V. G. K. Menta
Manufacturing Of High Performance Composites Using Vacuum Assisted Resin Transfer Molding, V. G. K. Menta
Masters Theses
"The objective of this research is to establish and enhance the existing Vacuum Assisted Resin Transfer Molding (VARTM) process to manufacture high performance composite parts usable in the aerospace industry.
Flat, hat, pi and multi stiffened panels have been manufactured by the VARTM process using AS4-5HS and AS4-8HS carbon fabric, and SI-ZG-5A low viscosity epoxy resin. Silicone-based reusable molds have been designed and developed to manufacture stiffened panels. Dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC) experiments of the SI-ZG-5A resin system were conducted to determine the storage modulus, loss modulus, and the glass transition temperature. The density and …
Mechanical Integrity And Behavior Of Thin Films And Their Applications In Mems, Gang Duan
Mechanical Integrity And Behavior Of Thin Films And Their Applications In Mems, Gang Duan
Doctoral Dissertations
"Electric actuated thin films are widely used in micro-electromechanical systems (MEMS) such as radio frequency switches (RF-switches), micro-pumps and valves, and electrostatic actuators. This dissertation will focus on the operation of a MEMS-RF-switch. In a typical MEMS-RF-switch, a mechanically suspended 1-D rectangular or 2-D axisymmetric thin film is pulled by an electrostatic voltage (V₀) applied to an electrode-pad directly underneath. When V₀ exceeds a certain "pull-in" threshold, V₀*, the thin film makes direct contact with the pad so that either an "on" or "off" signal is induced, and when the voltage is removed, the thin film resumes its original undeformed …
E-Design Tools For Friction Stir Welding: Cost Estimation Tool, Pradeep Kumar Tipaji
E-Design Tools For Friction Stir Welding: Cost Estimation Tool, Pradeep Kumar Tipaji
Masters Theses
"A cost model is an important tool for product design and material selection. An efficient and effective cost estimation tool is necessary for early design evaluation. In this paper, cost estimation models that estimate the production cost for Metal Inert Gas (MIG), Friction Stir (FS), and Friction Stir Spot (FSS) welded joints are presented. These models determine the cost incurred to fabricate each joint along with a detailed explanation of each cost component. Each cost component has been closely analyzed and major cost components have been included in the cost model"--Abstract, page iv.
Liquid Crystal Thermography Studies In Water Pool Boiling At Subatmospheric Pressures, Kiran Talari
Liquid Crystal Thermography Studies In Water Pool Boiling At Subatmospheric Pressures, Kiran Talari
Electronic Theses and Dissertations
A pool boiling experimental facility has been designed and built to investigate nucleate pool boiling in water under sub atmospheric pressure. Liquid crystal thermography, a non intrusive technique, is used for the determination of surface temperature distributions. This technique uses encapsulated liquid crystals that reflect definite colors at specific temperatures and viewing angle. Design of the test section is important in this experimental study. Since a new TLC is required for every new set of test conditions, a permanently sealed test section is not an option. The real challenge is to design a leak proof test section which is flexible …
Robust Positively Invariant Cylinders In Constrained Variable Structure Control, Hanz Richter, Brian D. O'Dell, Eduardo A. Misawa
Robust Positively Invariant Cylinders In Constrained Variable Structure Control, Hanz Richter, Brian D. O'Dell, Eduardo A. Misawa
Mechanical Engineering Faculty Publications
This paper proposes the use of cylinders as primary invariant sets to be used in certain state-constrained control designs. Following the idea originally introduced by O'Dell, the primary invariant set is intersected with the state constraints to yield sets which retain the invariance under some conditions. Although several results presented here apply to fairly general nonlinear systems and primary invariant sets of any shape, the focus is on constrained sliding-mode control (SMC) using infinite cylinders as the primary invariant set. Their use is motivated by a coordinate transformation where the sliding motion is decoupled from the overall convergence to the …
Modeling Failures Of Thermal Barrier Coatings, Anette M. Karlsson
Modeling Failures Of Thermal Barrier Coatings, Anette M. Karlsson
Mechanical Engineering Faculty Publications
Thermal barrier coatings are commonly used in high temperature parts of gas turbines, to protect the underlying metal substrate from deterioration during high temperature exposure. Unfortunately, the coatings fail prematurely, preventing the design engineers to fully utilize their implementation. Due to the complexity of the coatings, there are many challenges involved with developing failure hypotheses for the failures. This paper reviews some aspects of the current stateof- the-art on modeling failures of thermal barrier coatings, focusing on mechanics based models (such as finite element simulations) where the material physics is incorporated (such as oxidation and diffusion).
Time-Economic Lifetime Assessment For High Performance Thermal Barrier Coating Systems, Marion Bartsch, Bernd Baufeld, S. Dalkilic, Iulian Mircea, K. Lambrinou, T. Leist, J. Yan, Anette M. Karlsson
Time-Economic Lifetime Assessment For High Performance Thermal Barrier Coating Systems, Marion Bartsch, Bernd Baufeld, S. Dalkilic, Iulian Mircea, K. Lambrinou, T. Leist, J. Yan, Anette M. Karlsson
Mechanical Engineering Faculty Publications
Strategies for time-economic lifetime assessment of thermal barrier coatings (TBC) in service are described and discussed on the basis of experimental results, achieved on material systems with coatings applied by electron beam physical vapour deposition. Service cycles for gas turbine blades have been simulated on specimens in thermo-mechanical fatigue tests, accelerating the fatigue processes by an increase of load frequency. Time dependent changes in the material system were imposed by a separate ageing, where the samples were pre-oxidized prior to the fatigue test. Results of thermo-mechanical fatigue tests on pre-aged and as-coated specimens gave evidence of interaction between fatigue and …
Theoretical Exploration Of Characteristics Of Up-Conversion Materials In Photovoltaics, Joel Bordewyk
Theoretical Exploration Of Characteristics Of Up-Conversion Materials In Photovoltaics, Joel Bordewyk
The Journal of Undergraduate Research
Up-conversion materials can be used to greatly enhance the productivity of photovoltaic nanotechnologies. These materials must convert photons from a low energy to a higher energy to fit within the acceptable range of the solar panel. Software is needed to compute the value of these energy levels and to find molecules that produce these values. It must first be determined if the software has these capabilities and if the results are trustworthy. Naphthalamide has been a molecule of interest and serves as a good starting point for these studies.
Using Underwater Remotely Operated Vehicles As An Engineering Education Tool, Hong Zhang, John Chen, Eric Constans
Using Underwater Remotely Operated Vehicles As An Engineering Education Tool, Hong Zhang, John Chen, Eric Constans
Mechanical Engineering
Starting in 2004, the Department of Mechanical Engineering at Rowan University introduced a new tool into its program: Remotely Operated Vehicles (ROVs). The tool is used at different aspects ofeducation. As a coursework project, graduating ME seniors researched, designed, built, competed and reported with underwater ROVs to assess their design skills before heading out to start their careers. It tests a wide range of engineering background in one single project and gauges the soft skills such as teamwork, self-learning, communication and evaluation. As a student research project, a multidisciplinary student team developed a robotic field ROV to help biological scientists …
Wall Heat Transfer Effects In The Endwall Region Behind A Reflected Shock Wave At Long Test Times, Corey Frazier
Wall Heat Transfer Effects In The Endwall Region Behind A Reflected Shock Wave At Long Test Times, Corey Frazier
Electronic Theses and Dissertations
Shock-tube experiments are typically performed at high temperatures (≥1200K) due to test-time constraints. These test times are usually ~1 ms in duration and the source of this short, test-time constraint is loss of temperature due to heat transfer. At short test times, there is very little appreciable heat transfer between the hot gas and the cold walls of the shock tube and a high test temperature can be maintained. However, some experiments are using lower temperatures (approx. 800K) to achieve ignition and require much longer test times (up to 15 ms) to fully study the chemical kinetics and combustion chemistry …
Heat Transfer In Multi-Layer Energetic Nanofilm On Composites Substrate, Manesh Navid Amini
Heat Transfer In Multi-Layer Energetic Nanofilm On Composites Substrate, Manesh Navid Amini
Electronic Theses and Dissertations
The main purpose of this work is the physical understanding and the numerical description of the reaction of the dense metastable intermolecular composition (MIC). Energy density of MIC is much higher than conventional energetic material; therefore, MIC finds more applications in the propellant and explosive system. The physical model includes the speed of propagation and rate of reaction, and the relationship between the layer thickness, heat rate, and length of the flame based on physical model. In Part I of this thesis, a one-dimensional model based on Weihs was developed for 20 pairs of a multi-layer of aluminum and copper …
A Study Of Syngas Oxidation At High Pressures And Low Temperatures, Danielle Marie Kalitan
A Study Of Syngas Oxidation At High Pressures And Low Temperatures, Danielle Marie Kalitan
Electronic Theses and Dissertations
Ignition and oxidation characteristics of CO/H2, H2/O2 and CO/H2/CH4/CO2/Ar fuel blends in air were studied using both experimental and computer simulation methods. Shock-tube experiments were conducted behind reflected shock waves at intermediate temperatures (825 < T < 1400 K) for a wide range of pressures (1 < P < 45 atm). Results of this study provide the first undiluted fuel-air ignition delay time experiments to cover such a wide range of syngas mixture compositions over the stated temperature range. Emission in the form of chemiluminescence from the hydroxyl radical (OH*) transition near 307 nm and the pressure behind the reflected shock wave were used to monitor reaction progress from which ignition delay times were determined. In addition to the experimental analysis, chemical kinetics calculations were completed to compare several chemical kinetics mechanisms to the new experimental results. Overall, the models were in good agreement with the shock-tube data, especially at higher temperatures and lower pressures, yet there were some differences between the models at higher pressures and the lowest temperatures, in some cases by as much as a factor of five. In order to discern additional information from the chemical kinetics mechanisms regarding their response to a wide range of experimental conditions, ignition delay time and reaction rate sensitivity analyses were completed at higher and lower temperatures and higher and lower pressures. These two sensitivity analyses allow for the identification of the key reactions responsible for ignition. The results of the sensitivity analysis indicate that the ignition-enhancing reaction H + O2 = O + OH and hydrogen oxidation kinetics in general were most important regardless of mixture composition, temperature or pressure. However, lower-temperature, higher-pressure ignition delay time results indicate additional influence from HO2- and CO- containing reactions, particularly the well-known H + O + M = HO2 + M reaction and also the CO + O + M = CO2 + M and CO + HO2 = CO2 + OH reactions. Differences in the rates of the CO-related reactions are shown to be the cause of some of the discrepancies amongst the various models at elevated pressures. However, the deviation between the models and the experimental data at the lowest temperatures could not be entirely explained by discrepancies in the current rates of the reactions contained within the mechanisms. Additional calculations were therefore performed to gain further understanding regarding the opposing ignition behavior for calculated and measured ignition delay time results. Impurities, friction induced ionization, static charge accumulation, boundary layer effects, wall reaction effects, and revised chemical kinetics were all considered to be possible mechanisms for the model and measured data disparity. For the case of wall-reaction effects, additional shock-tube experiments were conducted. For the remaining effects listed above, only detailed calculations were conducted. Results from this preliminary anomaly study are at this time inconclusive, but likely avenues for future study were identified. Additional kinetics calculations showed that the large difference between the experimental data and the chemical kinetics models predictions at low temperatures can be explained by at least one missing reaction relevant to low-temperature and high-pressure experimental conditions involving the formation of H2O2, although further study beyond the scope of this thesis is required to prove this hypothesis both theoretically and experimentally.
An Interactive Framework For Meshless Methods Analysis In Computational Mechanics And Thermofluids, Salvadore Anthony Gerace
An Interactive Framework For Meshless Methods Analysis In Computational Mechanics And Thermofluids, Salvadore Anthony Gerace
Electronic Theses and Dissertations
In recent history, the area of physics-based engineering simulation has seen rapid increases in both computer workstation performance as well as common model complexity, both driven largely in part by advances in memory density and availability of clusters and multi-core processors. While the increase in computation time due to model complexity has been largely offset by the increased performance of modern workstations, the increase in model setup time due to model complexity has continued to rise. As such, the major time requirement for solving an engineering model has transitioned from computation time to problem setup time. This is due to …
Lattice Boltzmann Simulation To Study Single And Multi Bubble Dynamics, Amit Gupta
Lattice Boltzmann Simulation To Study Single And Multi Bubble Dynamics, Amit Gupta
Electronic Theses and Dissertations
In recent years, the lattice Boltzmann method (LBM) has emerged as a powerful tool that has replaced conventional macroscopic techniques like Computational Fluid Dynamics (CFD) in many applications. The LBM starts from meso- and microscopic Boltzmann's kinetic equation to determine macroscopic fluid dynamics. The origins of LBM can be drawn back to lattice gas cellular automata (LGCA); however it lacks Galilean invariance and creates statistical noise in the system. LBM on the other hand does away from these drawbacks of LGCA, and is easy to implement in complex geometries and can be used to study microscopic flow behavior in complex …
The Nature Of Turbulence In A Narrow Apex Angle Isosceles Triangular Duct, Vaidyanathan Krishnan
The Nature Of Turbulence In A Narrow Apex Angle Isosceles Triangular Duct, Vaidyanathan Krishnan
Electronic Theses and Dissertations
An experimental investigation was performed to ascertain the nature of turbulence in a narrow apex angle isosceles triangular duct. The study involved the design and construction of a low noise, low turbulence wind tunnel that had an isosceles triangular test section with an apex angle of 11.5[degrees]. Experiments involved the measurement of velocity fluctuations using hot wire anemometry and wall pressure fluctuations using a condenser microphone. Measurement of the velocity fluctuations reconfirms the coexistence of laminar and turbulent regions at a given cross section for a range of Reynolds numbers. The laminar region is concentrated closer to the apex while …
Methods Of Extrapolating Low Cycle Fatigue Data To High Stress Amplitudes, David Charles Radonovich
Methods Of Extrapolating Low Cycle Fatigue Data To High Stress Amplitudes, David Charles Radonovich
Electronic Theses and Dissertations
Modern gas turbine component design applies much effort into prediction and avoidance of fatigue. Advances in the prediction of low-cycle fatigue (LCF) cracks will reduce repair and replacement costs of turbine components. These cracks have the potential to cause component failure. Regression modeling of low-cycle fatigue (LCF)test data is typically restricted for use over the range of the test data. It is often difficult to characterize the plastic strain curve fit constants when the plastic strain is a small fraction of the total strain acquired. This is often the case with high strength, moderate ductility Ni-base superalloys. The intent of …