bluuebunny/crossref_metadata_2025_split huggingface dataset:
Real Time Monitoring and Simulation of Thermal Deformation in Plastic Package
Authors: Zhu Jiansen , Zou Daqing , Liu Sheng 
Published: March 2022

Abstract
Thermally-induced failure is a major reliability issue for electronic packaging. Due to highly nonlinearity of packaging materials, the electronic packages exhibit uneven thermal deformation in the whole temperature range during thermal cycling. This behavior will affect the buildup of thermal strain and thermal stress within packages, which may affect the reliability of the packaging. Therefore, a real time method is needed to monitor the thermal deformation of packages during the thermal cycling. In this study, the real time moiré interferometry technique is used to monitor the thermal deformation of a plastic package. A grating is transferred onto the cross section of the sample at room temperature. Then the sample is placed in a thermal vacuum chamber and the temperature is increased from room temperature to high temperature. A moiré interferometry setup is used to monitor the thermal deformation of the package with the increase of temperature. The fringe patterns are recorded by a CCD camera system and are compared with the displacement contours of nonlinear finite element simulations. The results show that the real time moiré interferometry technique is an effective way to monitor the thermal deformation of electronic packaging and also provide a powerful validation method for finite element analysis. The comparison between the moiré fringe patterns and finite element results also shows a good agreement.
Modeling Stresses of Contacts in Wiresaw Slicing of Polycrystalline and Crystalline Ingots: Application to Silicon Wafer Production
Authors: Li Ji , Kao Imin , Prasad Vish 
Published: March 2022

Abstract
Wiresaw is a cost-effective technology with high surface quality for slicing large diameter silicon wafers. Though wiresaws have been deployed to cut polycrystalline and single crystal silicon ingot since early 1990s, very little is known about the fundamental cutting process. We investigate this manufacturing process and propose a contact stress model of wiresaw slicing which illustrates the interactions among the wire, ingot, and abrasives (e.g., SiC) carried by the slurry. Stresses created by wiresaw slicing silicon wafers are analyzed in this paper. During the cutting process, the wire moves at high speed (5–15 m/s) with respect to the silicon ingot. The abrasives in the slurry are lose third-body particles caught between the wire and ingot at the contact surface. The forces applied by the wire carry the abrasive particles and cause them to roll on the surface and at the same time to be constrained to indent the surface. Such rolling-indenting interactions result in the formation of isolated chips and surface cracks. The cracks and discontinuity on the surface also cause high stress concentration. As a result the material is cut and removed. The stress fields of a single circular cone of the abrasive particle indenting on silicon crystal with normal and tangential forces can be calculated and analyzed from the modeling equations and boundary conditions. The stresses are expressed with dimensionless stress measures, as functions of normalized geometric parameters. The results show that the maximum normal stress occurs at the indentation point while the maximum shear stress (σzx) occurs below the surface of contact, as expected. Such subsurface shear facilitates the peeling effects of the silicon cracks. Both the normal and tangential forces applied at the contacts are incorporated in the model. The model is very effective in explaining and predicting the behaviors and distributions of stresses during the cutting process, and can be used to determine the optimal geometry of the abrasive particles in the rolling-indenting process.
Effect of Process Parameters on Chip Morphology When Machining Hardened Steel
Authors: Kishawy Hossam. A. , Elbestawi Mohamed. A. 
Published: March 2022

Abstract
This paper presents an experimental study of the effect of process parameters on chip morphology when machining hardened steel. Cutting tests are performed using ceramic inserts at (90–200) m/min cutting speed, (0.01–0.2) mm feed and (0.2–4) mm depth of cut. The chips obtained are examined using SEM and optical microscope. The effect of tool wear and different combinations of cutting speed and feed on chip morphology are studied. In addition, the effects of cutting conditions on chip segmentation frequency are investigated. Microhardness tests are also performed on the chips collected at different cutting conditions. The results obtained show that the cutting process parameters alter significantly the chips microhardness distribution.
Numerical and Experimental Analysis of Orthogonal Metal Cutting
Authors: Kalhori Vahid , Lundblad Mikael , Lindgren Lars-Erik 
Published: March 2022

Abstract
This paper presents experimental results which can be used for evaluating computational models to assure robust solutions. The general finite element code ABAQUS/Standard has been used in the simulations. A quasi-static simulation with adiabatic heating was performed. The path for separating the chip from the work piece is predetermined. The agreement between measurements and calculation is good considering the simplifications introduced. Still, some capabilities are lacking in ABAQUS. Work is continuing in order to create and evaluate more advanced computational models.
The Bending Moment as the Cause of Chip Formation
Authors: Astakhov Viktor P. , Shvets Stanislav V. , Osman M. O. M. 
Published: March 2022

Abstract
This paper presents a new study of chip formation in orthogonal cutting. The work has shown that the known model of chip formation based on the analytical description of the shear process alone has already reached its maximum development and still matches practical results only occasionally. Therefore, the further progress in the cutting theory may be achieved only by introducing some other mechanisms to account for the phenomena in the deformation zone. Naturally, this new mode of deformation should be considered together with shearing to explain the chip formation. This paper aims to introduce the bending moment as a cause of chip formation. The presence and the significance of the bending moment in the chip formation process have been demonstrated both theoretically and experimentally.
Role of Unloading in Machining of Brittle Materials
Authors: Chandra A. , Wang K. , Huang Y. , Subhash G. 
Published: March 2022

Abstract
A simple stress based defect evolution model is developed to assess the influence of various process paramters on material removal rate (MRR) and induced damage during ceramic grinding processes. Model predictions for normal and lateral damage zones under normal indentations are first compared to fracture models as well as experimental observations on pyrex glass. The proposed model is then extended to simulate oblique indentation events depicting abrasive gritworkpiece interactions during ceramic grinding. It is also easily extendable to real grinding situations involving multiple interacting abrasive grits. Process design options for reducing induced damage in the finished part, and increasing MRR are considered next. In particular, the potential of a new design avenue involving intermittent unloading is investigated. For pyrex glass, it is observed that intermittent unloading can facilitate significant increase in force per abrasive grit without increasing the associated surface and sub-surface fragmentation in the finished part. This design feature may enable significant increase in MRR, while maintaining a very low level of process induced damage in the finished product.
Material Constitutive Modeling Under High Strain Rates and Temperatures Through Orthogonal Machining Tests
Authors: Lei Shuting , Shin Yung C. , Incropera Frank P. 
Published: March 2022

Abstract
This paper presents a procedure to characterize deformation behavior applicable to various engineering materials in machining processes. Orthogonal machining tests are used to obtain the relationship between shear stress, strain, strain rate and temperature. Shear plane temperature is measured by an infrared thermal imaging system and compared with the Loewen and Shaw model. A new procedure to determine strain rate in the shear zone is proposed based on a triangular shear zone model and grain boundary determined by optical microscopy. Finally, a constitutive model for a low carbon steel, determined by the procedure, is presented and compared with existing results.
An Improved Analytical Modeling of Force System in Ball-End Milling
Authors: Lazoglu Ismail , Liang Steven Y. 
Published: March 2022

Abstract
The objective of this paper is to present a comprehensive algebraic model for better understanding of the cutting force system in the ball-end milling process. This objective is accomplished by analytically formulating the dominant dynamic components of three dimensional cutting forces in the machining of parts with helical multi-flute ball-end milling cutters. In this formulation, the effects of tool geometry, material characteristics, machining configurations, cutter-workpiece interactions, process parameters are quantitatively and explicitly presented. In this improved formulation, the axis inclination in the generation of 3-D sculpture surfaces is also incorporated to the force model, and the cutting force coefficients are predicted from the average chip thickness.
Tool Wear Characteristics of CBN Tools in the Finish Machining of Tool Steels
Authors: Sista Prasad S. , Swain Selden O. , Chandrasekar Srinivasan , Farris Thomas N. 
Published: March 2022

Abstract
A study has been made of the wear characteristics of CBN tools in the dry and wet finish machining of M2 tool steel, heat treated to a hardness of 60–62 Rc. The repeatability of CBN tool flank wear, the Taylor tool life exponent for CBN tools, the effect of coolant on tool wear and tool life, and the variation of component surface finish and cutting forces with tool wear have been measured. It is found that the evolution of tool wear is very repeatable, the Taylor tool life exponent for CBN tools is 0.26 in dry finish machining and that the use of a coolant leads to a 20–25% increase in tool life. The variation of surface finish with flank wear is also observed to be qualitatively similar in multiple cutting experiments carried out at the same conditions in dry and wet machining. The machining forces show a steady increase with flank wear with the radial force showing the greatest increase. The specific cutting energy for the CBN finish machining of M2 steel has been estimated and it is found to be about 10 times smaller than the specific grinding energy.
A 3-D Kinematic Model of Complex Chip Curling With Chip Breaker Tools in Metal Cutting: Part II — Analysis and Discussion
Authors: Fang Y. J. , Basu A. , Fang X. D. 
Published: March 2022

Abstract
Based on the 3-D analytical model of chip curling developed in the part I of this paper [1], a systematically theoretical analysis and further discuss have been done in this part by differentiating the model with respect to three chip angular velocity components ωx, ωy, ωz and chip flow angle η0 for the effects of the three chip angular velocity components. Based on the analysis, a group of criterions for the effects of ωx, ωy, ωz and η0 on the chip forms/shapes is obtained, and the varying tendency of the chip radius and chip pitch with varying ωx, ωy, ωz and η0 is discussed based on the group of criterions. Further, for better understanding, a group of 3-D diagrams has been given in order to visualise the varying tendency of the chip forms/shapes with the three chip angular velocity components and chip flow angle. The results of the analysis and discussion reveal that the chip twisting is an effective approach to chip breaking, specially for the thin chip breaking. These are significant in theory to direct the geometric design of the chip breaker/groove and effective control of chip breaking process.
Delayed Resonance Yields a New Perspective on Regenerative Machine Tool Chatter
Authors: Olgac Nejat , Hosek Martin 
Published: March 2022

Abstract
A well known phenomenon, regenerative machine tool chatter, is studied from an unconventional perspective. The fundamental reason for this undesired sustained oscillation is the selection of the cutting parameters such that the tool/workpiece interface acts like a resonator. Pure time delay which appears in the governing dynamics yields transcendental characteristic equations which possess infinitely many roots. The dominant roots among them should be searched. This work addresses the problem with a parallelism to a recent active vibration absorption methodology: the Delayed Resonator. Pursuing the root locus plot analysis it can be shown that the chatter can be reached for any cutting speed for a particular chip property. Very critically, we show that there are speed and chip width settings which yield regenerative chatter with dual frequencies. This particular feature parallels the basic claim of a recently patented technique for dual frequency vibration suppression.
Stability Analysis in Face Milling Operations: Part 1 — Theory of Stability Lobe Prediction
Authors: Jensen Steve A. , Shin Yung C. 
Published: March 2022

Abstract
This paper involves development of an algorithm to predict stability lobes in face milling operation. The modeling is based on frequency domain analysis and is comprehensive. It considers the effects of insert and cutter geometry, cutting conditions, process non-linearity, entry and exit angles and the fully dimensional structural dynamics of both the machine tool and workpiece, including axial dynamics which are often neglected by many researchers. In addition, the predictive capability of stability lobes by the presented models is compared with those results obtained by time domain simulations.
A Methodology for Early Front End Structural Design to Meet Safety Requirements Using CAE Tools
Authors: Wang Han , Johnson David , Hammoud Hassen , Bakkar Jamal 
Published: March 2022

Abstract
A methodology was developed to design the front end structure of a car with a short front-end to meet Frontal Impact safety requirements. The methodology is based on CAE tools, and it is to be applied in the early stages of the design process. It includes setting the vehicle target pulse, obtaining the component targets, designing the structural components and sub-systems, and evaluating the vehicle system by Finite Element analysis. The process is based in two CAE tools, an FCRASH Finite Element Hybrid model for the structural analysis, and a MADYMO model for the occupant simulation. The Hybrid model was chosen for the structural analysis in order to allow the upgrade of the CAE model during the different stages of the design process. Modifications of the process are discussed in order to meet different crash requirements.
Vehicle Interior Head Impact Simulations Using FCRASH
Authors: Barbat Saeed D. , Chou Clifford C. 
Published: March 2022

Abstract
The development of a finite element deformable featureless headform model for vehicle upper interior head impact simulations is described in this paper. The model and the head impact prediction methodology are developed using the FCRASH finite element code developed by Ford Motor Company. The model uses a visco-elastic material law which is implemented in FCRASH to simulate the vinyl skin response during impact. The constitutive parameters of the headform’s skin are calibrated through comparison of head drop simulations at various impact speeds with the corresponding tests. The predictions of the headform responses in drop tests at impact speeds of 2.68, 4.02, 5.36 and 6.71 m/s (6, 9, 12 and 15 mph) are in excellent agreement with related experiments.
In addition, the head impact prediction methodology development entails validations of simulation results against the test data in both component and full vehicle system environments. Interior head impacts at various locations on A-pillar, B-pillar, header and side rail are simulated. Comparisons of the predicted results with test data in terms of peak accelerations, Head Injury Criterion (HIC) and deceleration waveforms with test results are in close agreements. Application of this CAE tool to predict head impact response during product development is essential. Attribute trade-off study, and evaluations of A-pillar trim design alternatives and material candidates and identifying countermeasures for improved head impact protection are demonstrated. It is concluded that the developed head impact simulation methodology is capable of predicting the head response and HIC calculations during headform impact with vehicle upper interior.
Application of the Thermal Network Method to the Transient Thermal Analysis of Multichip Modules
Authors: Ishizuka Masaru , Iwasaki Hideo 
Published: March 2022

Abstract
In recent years, there is a growing demand to have smaller and lighter electronic circuits which have greater complexity, multifunctionality and reliability. High-density multichip packaging technology has been used in order to meet these requirements. The higher the density scale is, the larger the power dissipation per unit area becomes. Therefore, in the designing process it has become very important to carry out the thermal analysis. However, the heat transport model in multichip modules is very complex and its treatment is tedious and time consuming. This paper describes an application of the thermal network method to the transient thermal analysis of multichip modules and proposes a simple model for the thermal analysis of multichip modules as a preliminary thermal design tool. Based on the result of transient thermal analysis, the validity of the thermal network method and the simple thermal analysis model are confirmed.
The Record Power Profile of Male Professional Cyclists: Fatigue Matters
Authors: Mateo-March Manuel , Valenzuela Pedro L. , Muriel Xabier , Gandia-Soriano Alexis , Zabala Mikel , Lucia Alejandro , Pallares Jesús G. , Barranco-Gil David 
Published: March 2022

Purpose: The present study aimed to determine the influence of fatigue on the record power profile of professional male cyclists. We also assessed whether fatigue could differently affect cyclists of 2 competition categories. Methods: We analyzed the record power profile in 112 professional cyclists (n = 46 and n = 66 in the ProTeam [PT] and WorldTour [WT] category, respectively; age 29 [6] y, 8 [5] y experience in the professional category) during 2013–2021 (8 [5] seasons/cyclist). We analyzed their mean maximal power (MMP) values for efforts lasting 10 seconds to 120 minutes with no fatigue (after 0 kJ·kg−1) and with increasing levels of fatigue (after 15, 25, 35, and 45 kJ·kg−1). Results: A significant (P < .001) and progressive deterioration of all MMP values was observed from the lowest levels of fatigue assessed (ie, −1.6% to −3.0% decline after 15 kJ·kg−1, and −6.0% to −9.7% after 45 kJ·kg−1). Compared with WT, PT cyclists showed a greater decay of MMP values under fatigue conditions (P < .001), and these differences increased with accumulating levels of fatigue (decay of −1.8 to −2.9% [WT] with reference to 0 kJ·kg−1 vs −1.1% to −4.4% [PT] after 15 kJ·kg−1 and of −4.7% to −8.8% [WT] vs −7.6% to −11.6% [PT] after 45 kJ·kg−1). No consistent differences were found between WT and PT cyclists in MMP values assessed in nonfatigue conditions (after 0 kJ·kg−1), but WT cyclists attained significantly higher MMP values with accumulating levels of fatigue, particularly for long-duration efforts (≥5 min). Conclusions: Our findings highlight the importance of considering fatigue when assessing the record power profile of endurance athletes and support the ability to attenuate fatigue-induced decline in MMP values as a determinant of endurance performance.
Fluid-assisted brecciation of Lower Cretaceous Maiolica limestone in the Umbria-Marche Apennines: Hydrodynamical implications
Authors: Chan* Lung Sang , Alvarez Walter , Geiser Peter , Tavarnelli Enrico 
Published: March 2022

ABSTRACTThe formation of the “expansion breccia” observed in the Lower Cretaceous Maiolica limestone in the Umbria-Marches region of Italy is attributable to a fluid-assisted brecciation process that occurred during the late Miocene exhumation of the Northern Apennines. The hydrothermal fluids probably originated as brine solutions trapped in the Burano anhydrite while it was in a plastic state. The migration of the Burano from the plastic to the brittle domain during unroofing resulted in liberation and injection of over-pressured hydrothermal fluids into the overlying limestone, causing hydraulic fracturing. Mapping of breccia morphology along a 400-m transect showed structures produced by different flow regimes, with chaotic and mosaic breccia characterizing the core parts of the section and mineral-filled fractures and veins in the margins. Based on the clast size in the chaotic breccia, the estimated velocities for fluidizing the aggregates of clasts and sustaining the clasts in suspension are, respectively, 15 cm/s and 65 cm/s. Crack growth was probably the main mechanism for the fragmentation of the limestone. Explosion fracturing patterns were only sporadically observed in the breccia, indicating substantial heat loss of the over-pressured fluids during their ascent to the Earth’s surface.
Integrated stratigraphy of the Lutetian–Priabonian pelagic section at Bottaccione (Gubbio, central Italy): A proposal for defining and positioning the Global Stratotype Section and Point (GSSP) for the base of the Bartonian Stage (Paleogene System, Eocene Series)
Authors: Coccioni* Rodolfo , Montanari Alessandro , Boschi Samuele , Catanzariti Rita , Frontalini Fabrizio , Jovane Luigi , Kochhann Marcus Vinicius Lermen , Pelosi Nicola , Sabatino Nadia , Savian Jairo F. , Sprovieri Mario 
Published: March 2022

ABSTRACT
At present, the Global Stratotype Section and Point (GSSP) for the base of the Bartonian remains the only GSSP of the Paleogene System to be defined by the International Subcommission on Paleogene Stratigraphy (ISPS) and the International Commission on Stratigraphy (ICS). Here, we present the results of an integrated, high-resolution study of calcareous plankton and benthic foraminifera biostratigraphy and a detailed magneto-, chemo-, and cyclostratigraphic analyses carried out through the upper Lutetian to the upper Priabonian pelagic sediments of the Bottaccione Gorge section near Gubbio, central Italy, to check its stratigraphic completeness and constrain in time the optimal interval for defining and positioning the GSSP for the base of the Bartonian Stage. The high-resolution and solid integrated stratigraphic framework established at Bottaccione confirmed the completeness of the section, which meets the ICS recommendations for a potential designation as a GSSP for the base of the Bartonian Stage. Thus, the Bottaccione section was compared with the parastratotype section of the Bartonian in its type area, Alum Bay, UK. On this basis, two reliable criteria for defining and positioning the Bartonian GSSP at Bottaccione are provided: (1) the base of magnetic polarity chronozone C18r as the primary correlation criterion and (2) the base of the calcareous nannofossil Dictyococcites bisectus, which defines the CNE14/CNE15 zonal boundary as a secondary correlation criterion.