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The availability of reliable materials data is key to the successful design of materials and manufacturing processes. Commercial alloys rarely consist of only two or three elements, but rather may contain a large number of elements for which the needed
The NIST Materials Reliability Division is outfitting a high pressure (100 MPa) hydrogen testing facility to collect mechanical and thermodynamic property data on various candidate structural materials, and is developing data on nondestructive sensors that
Yifu Ding, Sebastian Pawlus, Alexei Sokolov, Jack F. Douglas, Alamgir Karim, Christopher Soles
We investigate the influence of adding C60 nanoparticles on the dielectric relaxation spectra of both unentangled and entangled polyisoprene (PIP). Relaxation modes corresponding to both segmental and chain relaxation were analyzed over a broad temperature
Jessica M. Torres, Christopher Stafford, Bryan D. Vogt
In this work, the modulus of polymer thin films for a homologous series of poly(n-alkyl methacrylate)s will be discussed. In particular, the impact of the degree of undercooling from bulk Tg on the deviations will be explored as Tg is significantly
Analysis of the structural and optical properties of gold- and copper-catalyzed zinc oxide (ZnO) nanowires (NWs), grown in a high temperature tube furnace on a sapphire substrate shows non-uniformity over the substrate. The changes in the optical
Jun Y. Chung, Thomas Q. Chastek, Michael J. Fasolka, Hyun W. Ro, Christopher Stafford
Residual stress, a pervasive consequence of solid materials processing, is stress that remains in a material after external forces have been removed. In polymeric materials, residual stress results from processes, such as film formation, that force and
Metal oxide fillers, such as titanium dioxide (TiO2), are heavily utilized in polymeric coatings and plastics for opacification, pigmentation, and mechanical enhancement. It is well known that the photoreactivity of TiO2 can contribute to the degradation
Joseph M. Antonucci, Anthony A. Giuseppetti, Justin N. O'Donnell, Gary E. Schumacher, Drago Skrtic
Objective: To assess the effect of the cavity design factor (C-factor) on polymerization stress development (PSD) in resin composites. Methods: An experimental resin (BT resin) was prepared, which contained 2,2-bis[p-(2 hydroxy-3 -methacryloxypropoxy
Igor Levin, Victor L. Krayzman, Joseph C. Woicik, J. Karapetrova, T. Proffen, M. G. Tucker, I. M. Reaney
Structural changes among the so-called M-polymorphs of AgNbO3 were analyzed using combined high-resolution X-ray diffraction, neutron total scattering, electron diffraction, and X-ray absorption fine structure measurements. These polymorphs crystallize
Over the years, NIST has been very active in adhesion research. Although there has never been an organizational group or large-scale program that focused specifically on this topic, a wide variety of projects have had adhesion, or related properties, as a
We develop two direct methods to simultaneously measure the dynamic capillary pressure and the viscosity of fluids by application of differential forces during flow into micro-channels. In the first method, a series of external pressures is applied in
We present a summary of Charpy impact verification test data that were evaluated by the National Institute of Standards and Tecnology (NIST) from January 1994 to December 1996. The Charpy impact machines that met the verification rule that limits the range
Dean M. DeLongchamp, Regis J. Kline, Youngsuk Jung, Eric K. Lin, Daniel A. Fischer, David J. Gundlach, Andrew Moad, Lee J. Richter, Michael F. Toney, Martin Heeney, Iain McCulloch
The carrier mobility of poly(2,5-bis(3-alkylthiophen-2-yl) thieno[3,2-b]thiophene) semiconductors can be substantially enhanced after heating through a thermotropic mesophase transition, which causes a significant improvement in thin film structural order
Adam J. Nolte, Jun Y. Chung, Marlon L. Walker, Christopher M. Stafford
Adhesion between materials is often governed by the ambient environment, which can mediate or change the types of molecular interactions present at an interface. Biological interactions, for example, can be mediated by factors such as temperature, ionic
Relaxation processes in viscous liquids and glasses have been studied extensively, but the underlying causes of glassy behavior in polymeric systems remains as a major unsolved area of condensed matter physics. These processes are critical in the
Jessica M. Torres, Christopher Stafford, Bryan D. Vogt
In this work, we will employ this wrinkling metrology to extract the modulus of polymer thin films for a homologous series of poly(n-alkyl methacrylate)s. In particular, we take advantage of the decrease in Tg as the alkyl chain length increases for these
The effect of specimen orientation and extrusion seam welds on the fatigue life of specimens milled from a hollow AA6063 alloy extrusion profile have been characterized in the form of S-N curves. The fatigue behavior of the fully recrystallized AA6063
Christopher L. Cromer, Katie Hurst, Xiaoyu X. Li, John H. Lehman
We describe a coating based on potassium silicate, commonly known as water glass, and multiwall carbon nanotubes. The coating has a high absorbance (0.96 at 1064 nm in wavelength) and a laser damage threshold that is comparable to that of ceramic coatings
Rafael L. Bowen, Gary E. Schumacher, Anthony A. Giuseppetti, Kathleen M. Flynn, Charles M. Guttman, Clifton M. Carey
Objectives. Determine bonding characteristics of a hydrophilic monomer formulation containing PCDs (Polymerizable Cyclodextrin Derivatives). The hypothesis was that a formulation containing hydrophilic cross-linking diluent comonomers and PCD molecules
Angelique N. Lasseigne, Kamalu Koenig, David Olson, Brajendra Mishra, Joshua Jackson, Thomas A. Siewert, Joseph D. McColskey
New higher strength pipeline steels (X100 and X120) exhibit lower tolerance for hydrogen (diffusible and formed hydrides) before significant degradation or failure occurs. It is essential to have advanced sensors to monitor the hydrogen content and
Joannie W. Chin, Sylvain H. Petit, Amanda L. Forster, Michael A. Riley, Kirk D. Rice
During routine field use of soft body armor, the ballistic panels often become saturated with perspiration. This condition motivates the user to clean and/or deodorize the armor, and anecdotal evidence is given for various methods used to accomplish this
Acoustic emission (AE) sources in a plate generate dispersive Lamb waves. In this research, pencil lead breaks (PLBs) were made on an edge of a 3.1 mm thick aluminum alloy plate to generate such AE waves. The PLBs were made near the plate midplane and near
Aaron M. Forster, Cyril Clerici, Donald L. Hunston
An efficient method to increase the Mode I fracture energy of a polymer adhesive is to incorporate a rubbery phase within the glassy matrix. In general, the failure surface of a toughened polymer is characterized by cavitated rubber particles and plastic