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in creator/contributor: "Maiya, P. S."

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Materials program plan for inertial confinement fusion

The effect of the irradiation environment on the microstructure of materials is studied. A major part of the initial activity in this area will be aimed toward evaluating the importance of pulse effects on microstructural development. The development effort that is necessary to cope with the high cycle loading of the first wall structure is studied. The loading pulses are expected to range from 1 to 20 per second (3 x 10/sup 7/ to 6 x 10/sup 8//year), thus creating a high cycle fatigue problem … more

Date: August 1, 1979

Creator: Garde, A.; Hall, B. O.; Harkness, S. D.; Maiya, P. S.; Rechtin, M. D. & Li, C. Y.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

A Unified and Mechanistic Approach to Creep-Fatigue Damage

A new creep-fatigue equation is proposed that takes into account both plastic strain and strain rate. The coefficients and exponents in the damage-rate equation are interpreted by means of the various damage mechanisms of the material. The damage-rate equation has been integrated to analyze various phenomena such as the effects of plastic strain rate on monotonic tensile or creep rupture time, rising mean strain on the low-cycle fatigue behavior at elevated temperature, tensile and compressive … more

Date: January 1976

Creator: Majumdar, S. & Maiya, P. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Application of Frequency-Modified Life Approach to the Low-Cycle Fatigue Behavior of Type 304 Stainless Steel

The application of the frequency-modified life equation to fatigue life prediction has been critically examined using the extensive fatigue data generated for Type 304 stainless steel at 1100 degrees F under a variety of cyclic-loading conditions. The parameters that enter into the frequency-modified life equation vary with strain rate and show a transition coinciding with the frequency of cycling at which a change in the fracture appearance from predominantly transgranular to predominantly int… more

Date: May 1976

Creator: Maiya, P. S. & Majumdar, S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Effects of Environment on the Low-Cycle Fatigue Behavior of Type 304 Stainless Steel

The low-cycle fatigue behavior of Type 304 stainless steel has been investigated at 593 degrees C in a dynamic vacuum of better than 1.3 x 10⁻⁶ Pa (10⁻⁸ torr). The results concerning the effects of strain range, strain rate and tensile hold time on fatigue life are presented and compared with results of similar tests performed in air and sodium environments. Under continuous symmetrical cycling, fatigue life is significantly longer in vacuum than in air; in the low strain range regime, the effe… more

Date: December 1979

Creator: Argonne National Laboratory. Materials Science Division.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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State-of-the-Art Review of Materials-Related Problems in Flue Gas Desulfurization Systems

This report characterizes the chemical and mechanical environments to which the structural components used in flue-gas desulfurization (FGD) are exposed. It summarizes the necessary background information pertinent to various FGD processes currently in use, with particular emphasis on lime/limestone scrubbing technology, so that the materials problems and processing variables encountered in FGD systems can be better defined and appreciated. The report also describes the materials currently used… more

Date: October 1980

Creator: Maiya, P. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Stress Corrosion Cracking of Candidate Waste Container Materials

Six alloys have been selected as candidate container materials for the storage of high-level nuclear waste at the proposed Yucca Mountain site in Nevada. These materials are Type 304L stainless steel (SS), Type 316L SS, Incoloy 825, P-deoxidized Cu, Cu-30%Ni, and Cu-7%A1. The present program has been initiated to determine whether any of these materials can survive for 300 years in the site environment without developing through-wall stress corrosion cracks, and to assess the relative resistanc… more

Date: November 1990

Creator: Maiya, P. S.; Soppet, W. K.; Park, J. Y.; Kassner, T. F.; Shack, W. J. & Diercks, D. R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Evaluation of stainless steel pipe cracking: causes and fixes

Leaks and cracks in the heat-affected zones of weldments in austenitic stainless steel piping and associated components of boiling water reactors (BWRs) have been observed since the mid-1960s. Since that time, cracking has continued to occur and indications have been found in all parts of the recirculation system, including the largest diameter lines. Proposed solutions include remedies primarily intended to produce a more favorable residual stress state, materials which are more resistant to s… more

Date: October 1, 1983

Creator: Shack, W. J.; Kassner, T. F.; Maiya, P. S.; Nichols, F. A.; Park, J. Y.; Ruther, W. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Environmentally assisted cracking in light water reactors

Cracking in sensitized austenitic stainless steel (SS) piping and associated components in boiling water reactors (BWRs) has been observed since the mid-1960s. Proposed remedies include procedures that produce a favorable residual stress state in the weld regions, replacement of the piping with materials that are more resistant to SCC, and modification of the reactor coolant environment. During this year, studies that have important implications for all three classes of proposed remedies have b… more

Date: August 1, 1987

Creator: Shack, W. J.; Kassner, T. F.; Maiya, P. S.; Park, J. Y.; Ruther, W. E.; Kuczay, T. M. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Creep-Fatigue Life Prediction for Different Heats of Type 304 Stainless Steel by Linear-Damage Rule, Strain-Range Partitioning Method, and Damage-Rate Approach

The creep-fatigue life results for five different heats of Type 304 stainless steel at 593 degrees C (1100 degrees F), generated under push-pull conditions in the axial strain-control mode, are presented. The life predictions for the various heats based on the linear-damage rule, strain-range partitioning method, and damage-rate approach are discussed. The appropriate material properties required for computation of fatigue life are also included.

Date: July 1978

Creator: Maiya, P. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Bilinear Cyclic Stress-Strain Parameters for Types 304 and 316 Stainless Steel

The bilinear cyclic stress-strain parameters for Types 304 and 316 stainless steel are described. The bilinear properties of solution-annealed and aged Type 304 stainless steel (heat 9T2796) and solution-annealed Type 3l6 stainless steel (heat 8092297) under cyclic-loading conditions at a strain rate of 8.6 x 10⁵ s⁻¹, total strain range between 0.2 and 0.8 percent, and temperatures from 22 to 593 degrees C were determined. The dependence of bilinear parameters on maximum strain epsilon and temp… more

Date: July 1978

Creator: Maiya, P. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Role of atmospheric corrosion of aluminum alloys in viability of intrinsic-surface methods for tagging military hardware

A primary requirement for authentication of tags for military equipment desigated as treaty-limited items (TLIs) is that the surface topograhy of the tag area be maintained after exposure to a variety of atmospheric conditions over many years. This report summarizes the chemical and physical properties of atmospheric as they relate to localized corrosion of aluminum and aluminum alloys. The role of impurity species that exacerbate corrison, and that hence may interfere with tag verification, is… more

Date: November 1, 1991

Creator: Maiya, P. S. & Kassner, T. F.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Dense Ceramic Membranes for Partial Oxygenation of Methane

The most significant cost associated with partial oxidation of methane to syngas is that of the oxygen plant. In this paper, the authors offer a technology that is based on dense ceramic membranes and that uses air as the oxidant for methane-conversion reactions, thus eliminating the need for the oxygen plant. Certain ceramic materials exhibit both electronic and ionic conductivities (of particular interest is oxygen-ion conductivity). These materials transport not only oxygen ions (functioning… more

Date: May 1, 1994

Creator: Balachandran, U.; Dusek, J. T.; Sweeney, S. M.; Mieville, R. L.; Maiya, P. S.; Kleefisch, M. S. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Ceramic membranes for generation of partial-oxidation products from methane

The most significant cost associated with partial oxidation of methane to syngas is that of the oxygen plant. In this paper, we offer a technology, based on dense ceramic membranes, that uses air as the oxidant for methane-conversion reactions and eliminates the need for an oxygen plant. Certain ceramic materials exhibit both electronic and ionic conductivities (of particular interest is oxygen-ion conductivity). These materials transport not only oxygen ions (functioning as selective oxygen se… more

Date: May 1, 1994

Creator: Balachandran, U.; Dusek, J. T.; Sweeney, S. M.; Mieville, R. L.; Maiya, P. S.; Kleefisch, M. S. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Damage equation for creep-fatigue interaction. [Total plastic strain, strain rate]

A damage equation for creep-fatigue interaction is proposed. Instead of separating total plastic strain into time-dependent and time-independent components or using frequency as the controlling parameter, the problem is cast in terms of the total plastic strain and strain rate as the fundamental variables. The damage equation can be integrated to analyze the time to failure for creep and creep-fatigue loading. The method is illustrated for Types 304 and 316 austenitic stainless steel, Incoloy 8… more

Date: January 1, 1976

Creator: Majumdar, S. & Maiya, P. S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Mechanical properties of vacuum-sintered equimolar CaO-Y{sub 2}O{sub 3} system

Dense composite material was fabricated aimed at pyrochemical container applications by vacuum-sintering an equimolar mixture of CaO and Y{sub 2}O{sub 3}. Its mechanical and physical properties were characterized: flexural strength, fracture toughness, thermal shock resistance, microstructure, density.

Date: April 1, 1991

Creator: Wagh, A. S.; Maiya, P. S.; Poeppel, R. B.; Russell, R.; Suratwala, T. & Roberts, D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Properties of TiN and TiN deposited by CVD on graphite for pyrochemical applications.

High-density TiN (>98% of theoretical) has been prepared by hot pressing TiN powder with 2-4 wt.% Li{sub 2}C0{sub 3} at temperatures between 1150-1550 C and pressures of {approx}40-50 MPa. The Li{sub 2}C0{sub 3} served as a fugitive sintering aid, enabling attainment of high density at low temperatures without adversely affecting the inherently good properties. Variation in processing variables and TiN powder characteristics resulted in material with various porosities. Measurement of mechan… more

Date: December 17, 1997

Creator: Maiya, P. S. & Moon, B. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Fabrication and characterization of dense ceramic membranes for partial oxidation of methane

In this technology, air is used as the oxidant for methane conversion reactions, thiu eliminating tne need for an expensive oxygen plant. Mixed-conducting ceramic materials have been produced from mixed-oxide system of the La-Sr-Fe-Co-O (SFC) type, in the form of tubes and bars. Thermodynamic stability of the tubes was studied vs oxygen partial pressure by high-temperature XRD. Mechanical properties of the SFC-2 (SrFeCo{sub 0.5}O{sub x}) material were adequate for reactor use. Electronic and io… more

Date: June 1, 1995

Creator: Balachandran, U.; Ma, B.; Dusek, J. T.; Picciolo, J. J.; Mieville, R. L.; Maiya, P. S. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Bilinear Cyclic Stress-Strain Analysis for Incoloy 800

This report describes the bilinear stress-strain analysis under cyclic loading conditions for the alloy Incoloy 800. Although the method for determining the bilinear stress-strain parameters is based on a procedure proposed in the RDT Standard F9-1 for inelastic analysis of Fast Flux Test Facility (FFTF) components, the accuracy and consistency of results have been improved by an analytical technique, which also resulted in certain simplifications. The bilinear stress-strain parameters of solut… more

Date: 1977?

Creator: Maiya, P. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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A Review of Degradation Behavior of Container Materials for Disposal of High-Level Nuclear Waste in Tuff and Alternative Repository Environments

Corrosion resistance of materials in aqueous systems is reviewed from the perspective of their suitability as container materials for nuclear waste. A discussion of the chemistry and characterization of repository environments, namely, tuff and alternative environments (shale, limestone, and carbonate), is followed by a description of corrosion mechanisms. In this review, emphasis is placed on localized corrosion (e.g., stress corrosion cracking, crevice corrosion, and pitting) because localize… more

Date: June 1989

Creator: Maiya, P. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Mixed-conducting dense ceramics for gas separation applications.

Mixed-conducting (electronic and ionic conducting) dense ceramics are used in many applications, including fuel cells, gas separation membranes, batteries, sensors, and electrocatalysis. This paper describes mixed-conducting ceramic membranes that are being developed to selectively remove oxygen and hydrogen from gas streams in a nongalvanic mode of operation (i.e., with no electrodes or external power supply). Ceramic membranes made of Sr-Fe-Co oxide (SFC), which exhibits high combined electro… more

Date: June 22, 1999

Creator: Balachandran, U.; Dorris, S. E.; Dusek, J. T.; Guan, J.; Liu, M.; Ma, B. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Dense ceramic membranes for converting methane to syngas

Dense mixed-oxide ceramics capable of conducting both electrons and oxygen ions are promising materials for partial oxygenation of methane to syngas. We are particularly interested in an oxide based on the Sr-Fe-Co-O system. Dense ceramic membrane tubes have been fabricated by a plastic extrusion technique. The sintered tubes were then used to selectively transport oxygen from air through the membrane to make syngas without the use of external electrodes. The sintered tubes have operated for >1… more

Date: July 1, 1995

Creator: Balachandran, U.; Dusek, J. T.; Picciolo, J. J.; Ma, B.; Maiya, P. S.; Mieville, R. L. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Use of porous MgO in pyrochemical applications

Pyrochemical methods for the extraction of transuranic elements from light water reactor spent fuel require a reduction step in which the oxide fuel is reduced to metals by Li in molten LiCl. The Li{sub 2}O formed is electrolytically reduced to metal in a cell that uses a carbon (or inert) anode and a Li cathode to recycle the salt and minimize the waste. Use of a carbon anode causes carbon dust that interferes with the process. Moreover, current efficiency is reduced as a result of oxidation o… more

Date: November 1, 1994

Creator: Maiya, P. S.; Sweeney, S. M.; Carroll, L. A. & Dusek, J. T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Technical basis for normal water chemistry guidelines: Review of laboratory studies of water chemistry effects on SCC (stress corrosion cracking)

The influence of dissolved oxygen, hydrogen, and various impurity anions on the stress corrosion cracking (SCC) susceptibility of sensitized Type 304 stainless steel (SS) and alternative piping materials such as Types 316NG and 347NG SS is being investigated in constant-extension-rate-tensile (CERT) tests and in cyclic loading experiments on fatigue precracked fracture-mechanics-type specimens at 289/sup 0/C. In these experiments, the crack growth behavior of the materials is being correlated w… more

Date: October 1, 1986

Creator: Kassner, T. F.; Maiya, P. S.; Park, J. Y.; Ruther, W. E.; Shack, W. J. & Soppet, W. K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Development of dense ceramic membranes for methane conversion

The most significant cost associated with partial oxidation of methane to syngas is that of the oxygen plant. In this paper, the authors offer a technology, based on dense ceramic membranes, that uses air as the oxidant for methane conversion reactions, thus eliminating the need for the oxygen plant. Certain ceramic materials exhibit both electronic and ionic conductivities (of particular interest is oxygen-ion conductivity). These materials transport not only oxygen ions (functioning as select… more

Date: June 1, 1995

Creator: Balachandran, U.; Dusek, J. T.; Maiya, P. S.; Ma, B.; Mieville, R. L.; Kleefisch, M. S. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department