bluuebunny/crossref_metadata_2025_split huggingface dataset:
Finite Element Simulations and Empirical Correlation for Charpy-V and Subsize Charpy Tests on an Unirradiated Low-Alloy RPV Ferritic Steel
Authors: Catherine CS , Poussard C , Vodinh J , Schill R , Hourdequin N , Forget P , Galon P 
Published: September 2009

Charpy-V test results are widely used for the surveillance program of RPV (Reactor Pressure Vessel) embrittlement by neutron irradiation. Service life extension of nuclear power plants and more stringent safety requirements are increasing the request for small test specimens such as subsize Charpy. Furthermore, the empirical correlation formulas between conventional Charpy-V and fracture toughness are often questionable. Therefore, prior to use of reduced size specimens, different hypotheses have to be validated and this can only be achieved by combining tests and finite element simulations. The material of interest is a nuclear RPV low alloy ferritic steel 16MND5 (eq. A508 C13). Instrumented impact tests were performed on Charpy-V and subsize Charpy over a wide range of temperatures. The hyperbolic tangent curve from W. Oldfield [1] was fitted to the results. Then, correlation formulas are evaluated and commented.
In a first step, the aim of the finite element simulations is to get a clear description of the global mechanical behavior of the specimens. A complete description of dynamic impact tests is not required for fracture mechanics purposes. A quasi-static simulation taking into account strain rate effect on the material response is sufficient. However, a 3D analysis is required even for cleavage failure mode. The second step is related to the transferability of fracture criteria. This task has been initiated at low temperatures using the Beremin cleavage model [2] and in the ductile regime using the Rousselier porous model [3]. The finite element results are compared to the experimental one. These results show good transferability potential.
Development of 5280 Rolling Bearing Steel for Improved Performance and Productivity
Authors: Dimitry PV , McDonough PJ , Beck G , Eberhard R , Zock HW 
Published: September 2009

A new optimized steel analysis has been developed in which the carbon and chromium are reduced and the manganese increased to improve the solidification during continuous casting. The aim of this new grade is a steel far more suitable for continuous casting than 52100 (100Cr6).
The bearing steel 52100 (100Cr6) has a proven track record throughout the world as the high carbon material of choice. With the increased production from the continuous casting process and the efficiencies of direct rolling, in combination with higher stress conditions for bearings, certain weaknesses have been recognized with the grade 52100 (100Cr6). Due to the high productivity rates of modern continuous casters, the long homogenizing cycles to minimize carbide segregation in 52100 are no longer practical. Without these long homogenizing cycles the result is more pronounced forms of segregation and adverse carbide distributions. These disadvantages can result in restricted mechanical and thermo-mechanical physical properties leading to difficulties in conventional and induction heat treatments.
The new grade under development can be classified 5280 (80CrMn4) and has been evaluated from both the steel production aspects as well as metallurgical behavior. With regard to the decisive properties of microstructure, life and processing the 5280 (80CrMn4) was equivalent to or better than the 52100 (100Cr6) steel. Continuous casting improved significantly; porosity, cracks or cavities were not present. The carbon segregation index was reduced. Carbide distributions measured according to SEP 1520 were at a minimum level, without excessive soaking prior to direct rolling. Heat treatment response was slightly modified to lower quenching temperatures, tempering at 220°C and 240°C resulted in the same values for hardness and retained austenite as in the case of 52100 (100Cr6). After martcnsitic heat treatment the hardness stabilization in 5280 (80CrMn4) required no process change from 52100 (100Cr6) to achieve the same degree of stabilization.
Mechanical properties of tensile strength, impact bending and notch impact strength; wear resistance and rotating bending strength were evaluated with direct comparisons to 52100 (100Cr6). Rolling contact fatigue tests were carried out on angular contact ball bearings of type 7205B where the inner rings were the test specimens. Test conditions were selected in such a way that it would be possible to make comparisons with 52100 (100Cr6) under diverse types of stress. The fatigue life of the 5280 (80CrMn4) was equivalent to the 52100 (100Cr6) base data.
Microstructural Optimisation of Bearing Steels for Operation Under Contaminated Lubrication by Using the Experimental Method of Dented Surfaces
Authors: Böhmer H-J , Eberhard R 
Published: September 2009

The damage mechanisms of antifriction bearings operating under debris contaminated lubrication have been investigated experimentally. A particular experimental procedure has been designed to simulate natural foreign particle indentations and to allow a quick reproducible fatigue test comparison on material and heat treatment variants. Additionally, the scattering of the fatigue test results could be reduced significantly.
The different phases of the damaging process are described. From these results measures have been derived to increase the bearing performance and lifetime under these stress conditions, which are governed by geometrical notch effects and localized metal-to-metal-contact and plastic deformation. The effectiveness in laboratory tests has been checked versus field applications.
An optimization of the materials microstructure was found to be an efficient means to counteract such problems. This was done by modifying the alloying content of the bearing steel and the surface composition respectively and changing the heat treatment in a way to generate a certain amount of very stable retained austenite. This particular microstructural component could be proved to have inherent self-healing capabilities against indentations produced by the overrolling of debris particles and the subsequent reflattening of the raised edges around the dents. This effect can be demonstrated by base-alloying of through-hardening grades as well as by surface alloying of case-hardenable steels.
The actual amount and the stability of the retained austenite against mechanical or thermal-induced transformation are important properties to achieve the tolerance to dent effects. Results of laboratory fatigue tests of different development routes and field experiences are presented. The consequences of these measures on the dimensional stability of the bearings are explained.
Development of a New Material for Guide Roll Bearings for Continuous Casting Machine
Authors: Yamamura K , Oohori M 
Published: September 2009

The guide roll bearings for a continuous casting machine (CCM) are used under extremely low rotation speed, high load, and debris-contaminated and water-infiltrated lubrication. Therefore, raceway surfaces usually wear severely and outer rings are sometimes fractured.
The purpose of this study is to prolong the CCM bearing life by material and heat-treatment technologies. We investigated the fracture process of CCM bearings and developed a new material, case hardened steel, that shows superior wear resistance to SAE 52100 steel. Optimum control of retained austenite and hardness extends rolling contact fatigue life under contaminated lubrication. In the simulation tests of a CCM guide roll, superior wear resistance was confirmed under water-infiltrated lubrication conditions.
The Effect of Bearing Steel Composition and Microstructure on Debris Dented Rolling Element Bearing Performance
Authors: Carlson D , Pitsko R , Chidester AJ , Imundo JR 
Published: September 2009

Because of continuous improvements in bearing steel cleanliness, surface damage created by debris has become more influential in determining the life of rolling element bearings. The metallurgical structure of a bearing raceway can be modified to optimize strength and damage tolerance. The correct balance between raceway strength and damage tolerance can significantly improve bearing life in contaminated environments.
Retained austenite is known to add a degree of damage tolerance to hardened bearing steel. Samples made of ASTM A295 52100 steel were heat treated to obtain increasing amounts of retained austenite. Indentations were placed into the steel sample surfaces using a Rockwell 30N Superficial Hardness Tester. These indentations were examined and measured using light interferometry. The changes in the dent morphologies with increasing amounts of retained austenite will be discussed.
A test program has been developed to investigate the influence of microstructure on the life of debris dented rolling element bearings. Groups of 35 mm bore radial ball bearings were dented with either a Rockwell 30N Superficial Hardness Tester, or with hard powder metal particles. These bearings were then fatigue tested with uniform contact stress, speed and clean lubricant with a marginal lubrication film. The performance of different bearing steels and heat treatments were investigated, and test results from the two denting methodologies will be provided.
In-Situ Dew-point Measurement to Assess Life Span of Insulating Glass Units
Authors: Torok GR , Lichtenberger W , Major A 
Published: September 2009

Replacement of insulating glass (IG) units in buildings is expensive. Replacement costs can be estimated fairly accurately. However, timing is less certain. In the author's experience, time estimates for replacement are often based on poor understanding of the causes of IG unit “failure” (water vapour condensation on glass surfaces facing the IG unit cavity) and previous negative experience, and thus are reactive rather than predictive.
The life span of insulating glass units in service is not well known. Insulating glass units have been made in North America since the late 1950s. Laboratory test methods developed in Canada in the late 1950s and early 1960s, subsequently used as the basis of most IG unit test methods worldwide, were intended to assess the likelihood of successful performance through the IG unit manufacturer's warranty period, not to determine service life span. In the 1980's, based on in-situ testing for the “Field Correlation Study” by the Sealed Insulating Glass Manufacturers Association (SIGMA) in the USA, Spetz proposed that one component of the laboratory test method, dew-point measurement of cavity gas fill, could be used to estimate time to failure of IG units in service. This technique is examined in this paper and modifications are suggested to improve accuracy.
Retrofitting Commercial Structures with Laminated Glass to Withstand Hurricane Effects
Authors: Beers PE , Pilcher MA , Sciaudone JC 
Published: September 2009

There is an enormous inventory of buildings in the United States. The majority of these buildings have not been designed to resist hurricane effects, namely high winds and windborne debris.
Commercial structures have a history of damage during previous hurricanes. Many large buildings in downtown Houston, Texas suffered extensive glass breakage during Hurricane Alicia in 1982. This was the first documented instance of windborne debris causing significant glass breakage in an urban area. Before Alicia, it was thought that high winds alone were responsible for hurricane damage. However, recently there have been several more instances of glass breakage during hurricanes have occurred, including the Kendall area in Dade County, Florida during Hurricane Andrew in 1992.
While mitigation efforts for newly constructed buildings are very important, this activity only benefits a small percentage of the built inventory. The vast majority of the built commercial building inventory is not protected. Without retrofitting, it will take many years before a significant percentage of commercial buildings are protected, even if all newly constructed buildings were designed for hurricane effects.
Protecting commercial structures from hurricane elements, namely wind and windborne debris, requires unique considerations. Many buildings have glass areas too large to accommodate shutters. Even if shutters can be employed it may be impractical to install them in advance of a storm. Often the best solution for a commercial building is to use impact-resistant laminated glass. With laminated glass, there is no special preparation required in advance of a storm as the protection is always in place. And, it provides invisible protection because it appears as ordinary window glass.
The use of laminated glass for hurricane protection requires special designs. Laminated glass is often thicker than ordinary window glass and it must be attached or anchored to the window frame so it remains in place, if broken. The challenge for retrofitting commercial windows with laminated glass is to find a cost-effective method that does not require replacement of the framing as well. This paper will present methodology for a cost-effective retrofit using laminated glass and the existing window frames.
The Relationship Between Sprinkler Systems and Glass
Authors: Razwick J 
Published: September 2009

This paper explores the particular relationship between sprinklers and glass in a building. There are many misconceptions about sprinklers' ability to prevent non-rated glass from breaking during a fire, when in fact sprinklers can actually cause some glass to break. Laboratory testing has shown that unless the conditions can be strictly controlled, sprinklers and non-rated glass are not an adequate combination to prevent the spread of a fire. Specific testing examples and illustrations are cited in the paper.
Sprinklers are also “active” systems, depending on proper maintenance and activation sequences in order to work properly, whereas fire-rated glass is a “passive” system providing compartmentation around the clock.
Evaluation and Remediation of Low Permeability and Dual Porosity Environments
Authors: Sara MN , Everett LG 
Published: September 2009

Description
This unique publication provides a global perspective on one of the most complex issues in hydrology: field and laboratory measurement of low permeability and dual porosity materials. Eleven peer-reviewed papers, written by an international group of experts, focus on the development of techniques to evaluate hydraulic conductivity and remediation of fine grained and dual porosity geologic materials.
It deals with a range of issues related to the measurement of both saturated and unsaturated geologic materials, including:
• Test Procedures
• Laboratory and Field Evaluations
• Low Permeability Environments and Remediation Issues
STP 1415 is a valuable resource for geologists, hydrologists, hydrogeologists, environmental and civil engineers, environmental scientists, waste management personnel, landfill owners and operators, and remediation specialists.
Composite Materials: Testing, Design, and Acceptance Criteria
Authors: Zureick A , Nettles AT 
Published: September 2009

Description
STP 1416 features 17 peer-reviewed papers covering various aspects of testing, design, and acceptance criteria for composite materials. Topics cover:
• NDT Evaluation
• Material Qualification
• Full-Scale Structural Testing
• Durability
• Test Method Development
• Micromechanics
• Damage Resistance and Tolerance
• Impact
• Bucking
Audience: STP is a valuable research tool for both the civil engineering infrastructure and aerospace communities.
Bearing Steel Technology
Authors: Beswick JM 
Published: September 2009

Description
STP 1419 provides the latest global information on bearing steel manufacture and service life endurance, along with an up-to-date perspective on rolling bearing steel technologies. 34 peer-reviewed papers cover:
Bearing Steel Process Developments reviews global bearing steel making technologies, including a description of a billet casting friendly steel grade. Topics also cover never-before published data on the relative segregation levels for ingot and continuously cast 1C-1.5Cr, bearing steel, the effect of steel making processing parameters, and the soaking practice on bearing steel segregation properties.
Steel Technology and Bearing Component Manufacture discusses the machinability parameters in bearing steels within the Swedish bearing industry and relevant testing methodologies. This section also covers modernistic steel technologies related to improved environmental aspects of the hardening heat treatment process.
Developments in Bearing Steel Quality Assessment and Correlation’s with Bearing Life examines the use of ultrasonic techniques for internal cleanliness assessment, the use of statistics of extreme values (SEV), and a new method based on generalized Pareto distribution (GPD) when using optical microscopy.
Developments in Bearing Service Life Testing covers rolling bearing service life, as opposed to "pure" rolling contact fatigue life testing.
Bearing Metallurgy Developments for Improved Service Life describes the technologies pertaining to new alloys, heat treatments and microstructure control for improved served life and extreme conditions.
Developments in High Alloy Steel for Improved High Temperature and Enhanced Corrosion Resistance Properties addresses the demand in the rolling bearing industry, particularly aerospace, for high temperature and corrosion resistance.
Microstructural Changes and its Relationships with Bearing Life and Life Time Predictions focuses on the material physics aspects associated with the Hertzian contact cyclic process in rolling bearing contacts.
Material Factors in Bearing Life Calculations deals with rolling bearing life endurance models.
Audience:
STP 1419 is a valuable resource for bearing and steel manufacturers and purchasers, bearing designers, researchers and technologists, and tribologists.
Repair, Retrofit and Inspection of Building Exterior Wall Systems
Authors: Boyd Jon M. , Johnson Paul G. 
Published: September 2009

Description
Eighteen peer-reviewed papers address the complex issues of design, construction, maintenance, evaluation, and repair of building exterior wall systems, both old and new.
Topics cover
System types addressed include facades comprised of vintage masonry, limestone, precast concrete panels, thin stone, exposed cast-in-place concrete, aluminum framing, EIFS, and glass and metal walls.
The Effect of Irradiation Temperature on the Post-Irradiation Stress-Strain Behavior of Stainless Steel
Authors: Martin W. R. , Weir J. R. 
Published: September 2009

This paper describes the results of an investigation of the influence of irradiation temperatures from 150 to 750 C, and post-irradiation test temperatures of 25 to 850 C on the mechanical properties of AISI Type 304 and 347 stainless steels tested at various strain rates. The irradiations were conducted in an Oak Ridge Research Reactor core position. Subsize tension specimens were irradiated to 7 x 1020 nvt (fast) and 9 x 1020 nvt (thermal).
The yield stress was not affected by irradiation at any test temperature above 600 C. At lower irradiation and testing temperatures the yield and ultimate engineering tensile stresses are strongly dependent upon irradiation temperature. The true tensile and fracture stresses at test temperatures below 600 C were unaffected regardless of the irradiation temperature; they were slightly reduced at test temperatures above 600 C in the high strain-rate tests.
Increases in yield strength due to irradiation were associated with decreases in the uniform elongation, but not fracture strain for test temperatures below 600 C. At higher testing temperatures the radiation effect on the ductility parameters was strongly strain-rate sensitive. The ductility parameters decreased markedly with decreasing strain-rate and increasing deformation temperature.
At this neutron exposure the influence of irradiation at deformation temperatures less than 600 C is reflected only in the stress-strain relationship and not in the fracture stress or strain. However, the irradiation effect for deformation at 600 C and above concerns the fracture process and not the deformation relationship. The effect on the fracture process appears to be a result of changes in the grain boundary fracture behavior.
In-Reactor Stress-Rupture Properties of a 20Cr-25Ni, Columbium-Stabilized Steel
Authors: Venard J. T. , Weir J. R. 
Published: September 2009

There is widespread interest in the effect of neutron bombardment on the mechanical properties of the austenitic stainless steels because of their frequent application in reactor structures and fuel claddings. For this reason, a columbium-stabilized austenitic stainless steel (20Cr-25Ni-bal Fe) developed in the United Kingdom for gas-cooled reactor service has been tested inreactor for its stress-rupture characteristics.
The tests were performed by internally pressurizing tubes at temperatures of 550, 650, 750, and 850 C in a neutron flux of approximately 5.0 x 1012 nv fast (&gt;2.9 Mev) and 6.0 13 1013 nv thermal. Duplicate tests were performed ex-reactor. Brief details of test procedures and a discussion of the experimental results are presented.
Only a small effect of irradiation on material strength was seen, but a strong effect of irradiation and temperature on the fracture ductility was observed.
In-Reactor Studies of Low-Cycle Fatigue Properties of a Nuclear Pressure Vessel Steel
Authors: Hawthorne J. R. , Steele L. E. 
Published: September 2009

This paper describes an experimental irradiation assembly and associated instrumentation which has been developed and successfully utilized for the performance of dynamic, in-reactor low cycle fatigue tests of reactor pressure vessel steels. The equipment provides for the simultaneous reverse bend testing of as many as 15 sheet-type specimens representing a range of strain amplitudes at controlled temperatures in the range of 300 to 700 F.
The results of an exploratory investigation on the fatigue resistance of ASTM A302-B steel during irradiation at 500 F are presented and compared with data from out-of-reactor control tests.
In-Reactor Creep of Cold-Worked Zircaloy-2
Authors: Holmes J. J. , Williams J. A. , Nyman D. H. , Tobin J. C. 
Published: September 2009

The creep properties of 20 per cent cold-worked Zircaloy-2 during neutron irradiation have been determined in the temperature range 275 to 465 C and stress range 20,000 to 35,000 psi. In general, the effects of neutron irradiation on creep are small; however, some differences between in-reactor and ex-reactor tests exist. The activation energy for creep during irradiation is around 90,000 cal/mole. In the absence of irradiation, the activation energy is about equal to the self-difiusion value of 60,000 cal/mole. During reactor outages, a small increase in creep rate occurs. The time required to initiate the increase after a shutdown decreases with increasing temperature.
During irradiation, steady-state creep rates can be expressed as ϵ·=2.5×1020exp(5.31×10-4σ)e-90,000/RT, where: ϵ = creep strain per hour, σ = stress in psi, T = absolute temperature, and R = the gas constant.
In addition, total creep strain prior to the first reactor outage can be expressed in terms of Dorn's parameter =S(σ)f[texp((−90,000)/RT)], where t = time.