Showing papers on "Blisters published in 2001"

Thermodynamic model of hydrogen-induced silicon surface layer cleavage

Abstract: A thermodynamic model of hydrogen-induced silicon surface layer splitting with the help of a bonded silicon wafer is proposed in this article. Wafer splitting is the result of lateral growth of hydrogen blisters in the entire hydrogen-implanted region during annealing. The blister growth rate depends on the effective activation energies of both hydrogen complex dissociation and hydrogen diffusion. The hydrogen blister radius was studied as a function of annealing time, annealing temperature, and implantation dose. The critical radius was obtained according to the Griffith energy condition. The time required for wafer splitting at the cut temperature was calculated in accordance with the growth of hydrogen blisters.

Unit for feeding articles to a blister band

Abstract: In a unit for feeding articles to a blister band, a casing has two apertures for a blister band to enter and come out of the casing. The casing supports and contains operative means for feeding articles to blisters made in the blister band. The casing is connected to a blistering machine for feeding the articles, and is removed from the blistering machine for cleaning and/or sterilizing the casing and the operative means in a suitable area.

Delamination behavior of Pt in a SiO2/Pt/Pb(ZrxTi1−x)O3/Pt ferroelectric thin-film capacitor

Abstract: Silicon dioxide was deposited on a Pt/Pb(ZrxTi1−x)O3/Pt capacitor by the plasma-enhanced chemical-vapor deposition (PECVD) method. We have been investigated the mechanism of blister formation on the PECVD SiO2/Pt/PZT/Pt capacitor. The blisters were observed at the temperature of 325 °C in O2 atmosphere, while in N2 and Ar atmosphere blisters were not formed even at 500 °C. Hydrogen evolution analysis from the PECVD SiO2 layer showed a sharp peak near 320 °C. The results indicated that the accumulation of water-vapor pressure developed by chemical reaction between oxygen and hydrogen could be the dominant mechanism of blister formation in PECVD SiO2/Pt/PZT/Pt capacitors.

Blister appearance in thermoplastic composites

Abstract: Blisters were observed in thermoplastic composite materials after a thermal shock during the manufacturing process of electronic parts. The aim of this paper is to describe the blister appearance and its mechanism. First, an experimental study is presented about the environmental conditions and the evolution of blister appearance on the specimen, then the mechanism of their formation and propagation in the material is suggested, and finally an attempt is made to explain the origin of the phenomenon. Experiments show that the water content of the material, the time and the temperature of the thermal shock play an important role. Observations made by SEM show the blister progression in the core of the material. A crack is initiated and then propagates on the interface fiber-matrix. After a crack reaches a sufficient length, the internal stress field opens it and a blister appears.

Energy-filtered image of surface blisters by grazing incidence electron microscopy

Abstract: We have examined fine structure of surface blisters formed by D + or He + irradiation onto mono-crystalline silicon by grazing incidence electron microscopy (GIEM), using an energy-filtering transmission electron microscope (EFTEM). Mapping of the projected thickness clearly visualized the structural difference of the blister skins formed by D + and He + irradiation respectively. A He distribution image of the He-blister was also successfully obtained.

Development of a pulse heating thermographic NDT technique for detection of latent blister in corrosion protective coating on oil storage tank

Abstract: Pulse heating thermographic NDT technique was developed for the detection of latent blisters in the corrosion protective coating on oil storage tanks employed for petroleum stockpiling in Japan. Experimental studies were made on the applicability of the proposed NDT method to the quantitative identification of the subsurface latent blisters in the coating. Pulse heat flux by the xenon flush lamp was applied to the surface of the corrosion protective coating and sequential thermal images were taken by the high-speed infrared thermography. It was found that the blisters were clearly identified as the localized high temperature region in the sequential thermal images.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Thermographic blister detection in frp strengthened rc elements and degradation effects on section performance

Abstract: This paper represents a progress report on the development of a technique to evaluate the extent of bonding success between advanced composites and concrete substrate. A new nondestructive evaluation method is presented for the detection of blisters at the interface of fiber reinforced polymer (FRP) and concrete. Artificial voids of controlled size were inserted in the bond line of composite bonded concrete specimens to simulate the potential creation of imperfections during site applications. A simple heat source was used to generate heat for dissipation in the FRP-concrete joint. An infrared camera was used to detect the heat transfer. It was found that the originally simulated 15mm diameter blisters could be clearly detected by the IR camera from 7.6m. This nondestructive approach is therefore considered to have great potential for use in FRP strengthening schemes. Alongside this work, beams with simulated blisters were load tested to failure. It was found that blisters of small magnitude do not fundamentally alter load/deformation characteristics, but seriously curtail ductility through premature failure.

Use of a blister package

Abstract: of EP1108413Blister pack for pharmaceutical tablets or capsules is contained in a cardboard sheet ( 4) which is folded over to form a top (6) and bottom (5) layer with the blister pack between. The blisters (3) protrude through openings (8) in the top sheet and the tablets can be pressed out through corresponding holes (9) in the bottom sheet. Independent claims are also included for: (1) use of the cardboard sheet for producing a blister pack containing a predetermined number of tablets or capsules; and (2) a blister pack containing a predetermined number of tablets or capsules.

The effect of oil type on blister formation in carbon-graphite mechanical seals©

Abstract: Blisters that are observed on carbon-graphite seal faces are created by a fracture process that derives from viscous friction forces present at the instant that relative rotation begins between seal faces. High speed data acquisition of shaft torque and shaft rotation data was used in this study to measure breakaway torque for different types of oils that were present between seal faces at startup. Synthetic polyalphaolefin oils create higher traction forces and a larger number of blisters than do mineral oils of comparable viscosity.

Ion irradiation induced spontaneous hypersonic long-range stimulation of silicon nitride synthesis in silicon

Abstract: We studied the nature of the effect of medium-energy ion implantation on the defect system of a crystal target over distances exceeding by three to four orders of magnitude the average projected range of ions in the target material. Recently, we discovered an especially strong manifestation of this long-range effect in crystal targets: argon ion bombardment stimulated the formation of a Si3N4 phase in nitrogen-saturated layers of a silicon wafer, the effect being observed at a distance of up to 600 μm away from the ion stopping zone. An analysis of changes in the electrical and optical properties of the nitrogen-saturated layer depending on the argon ion dose, in comparison to the morphology development on the ion-irradiated silicon surface, suggests that sufficiently effective pulsed sources of hypersonic (in the initial propagation stage) shock waves appear in the Ar+ ion stopping zone. These shock waves arise as a result of the jumplike formation and evolution of a network of dislocation loops and argon blisters, accompanied by explosions of the blisters. These processes probably proceed in a self-synchronized or spontaneous manner. Argon in the blisters occurs at T = 773 K in a solid state under a pressure of 4.5×109 Pa, the blister energy reaching up to 5×108 eV. Estimates show that the synchronized explosions of blisters in the region of a nitrogen-saturated layer at the rear side of a 600-μm-thick silicon wafer may produce a peak pressure at the wave front exceeding 108 Pa, which is sufficient to cause the experimentally observed changes.

The mechanism of blister formation on carbon-graphite mechanical seal faces

Abstract: Blister formation on carbon-graphite mechanical seal faces most commonly occurs in oil and hydrocarbon service, with higher viscosity oils, and with stop-start cycling. Blisters form unexpectedly, often with catastrophic results. In this study, an experimental apparatus that closely simlates field conditions was used to form blisters onfive different grades of carbon-graphite seal faces. The tests showed that blisters form at the instant of initial shaft rotation. Significantly more blisters form as the viscosity of the oil between the seal faces increases when chilled. The blisters are located randomly around the seal face and not in regular patterns. The authors conclude that blister formation is a mechanical process through which a shallow subsurface crack is formed by shear forces acting at the carbon-graphite seal face.

Feeding system designed for dry powder inhaler

Abstract: medicine SUBSTANCE: system for keeping and feeding of powder designed for powdered medicinal preparations has a carrying disk with a blister shell hermetically by the tearable layer A tag is attached to the tearable layer under the blister shell The carrying disk is placed in the dry powder inhaler The drive member presses the tag making the tearable layer open releasing the contents in the form of powdered medicinal preparation from the blister and ejecting it into the dry powder inhaler The carrying disk has breakable blisters with a brittle shell of the blisters thermowelded to the coating layer made of foil and coated with a plate The drive member is shifted to the plate making the plate bend, and the blister shell break, releasing the powdered medicinal preparation to the dry powder inhaler EFFECT: enhanced efficiency of powder feed 10 cl, 23 dwg

Blister package, device of and method of making blister packages

Abstract: packing. SUBSTANCE: blister package has film-backing with blisters and flat film-cover connected with backing. Package has at least two parallel rows of blisters with intermediate part provided with at least two bending lines parallel to above-indicated rows. Package can be folded along bending lines. Blisters of one row are displaced relative to blisters of other row coming in contact with each other at folding. Blisters of at least two rows in folded package are arranged on one line. Height of blisters corresponds to distance between outer lines of binding. Proposed package can be easily processed in manufacturing as, after folding of package, blisters "hide", making the package more stable. Device for producing blister package has mould for making film-backing with blisters provided with at least two rows of spaces. Spaces in one row are displaced relative to spaces in other row. It has also device for making two parallel bending lines in film-backing between rows, and blister package folding device for blister package, constructing of film-backing and film-cover, along bending lines. EFFECT: improved protection of blister content. 16 cl, 2 dwg

지르코늄 압력관에서 Hydride Blister에 의한 잔류응력 측정

Abstract: When the pressure tubes (PT) contact to the calandria tube (CT) in the pressurized heavy water reactor(PHWR), the temperature difference between inner wall and outer wall of PT results in a thermal diffusion of hydrogen (deutrium) and hydride blisters are formed on the outer surface of PT. The volume expansion associated with the formation and growth of zirconium hydride blister creates localized residual stresses in the PT. Residual stresses of localized area near the hydride blister were measured by micro-focused x-ray diffraction(XRD). The specimen were prepared using a cold spot on the outer surface of PT and the diameter of XRD beam was set as 100 ㎛. When we measured residual stress on the outer surface of PT, residual stress state of zirconium matrix just outside the blister were compressive and become tensile as moving to the inside the blister. The cross-sectional residual stress state of blister also revealed that compressive stress state at zirconium matrix just outside the blister and tensile stress state at the inside blister. These results are compared with the finite element model and discussed with the possibility of crack propagation to the zircoium matrix.