Influence of Temperature on Characteristics of TiAl Plasma Surface Niobiumizing

In this study, plasma niobium alloying of the TiAl based alloys has been carried out at 1050, 1100 and 1150°C. The effect of the alloying temperature on the characteristic of the alloyed layer was investigated by optical microscopy, scanning electronic microscopy (SEM), glow discharge spectrum (GDS) and energy dispersive spectrum (EDS). The results show that the surface roughness, chemical composition and thickness of the alloyed layer increased with the alloying temperature which is dependent on the sheath potential. A deposition layer formed on the TiAl surface at 1150 °C was resulted from the larger sheath potential or the stronger sputtering of source electrode.

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Effect of the Ratio of Zn/Y on Microstructure and Mechanical Properties of As-Cast Mg-4Zn-xY Alloys

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.395-396.201 ◽

2013 ◽

Vol 395-396 ◽

pp. 201-204

Author(s):

Feng Wang ◽

Ji Bao Li ◽

Ping Li Mao ◽

Zheng Liu

Keyword(s):

Mechanical Properties ◽

Tensile Testing ◽

Energy Dispersive Spectrum ◽

X Ray Diffraction ◽

Scanning Electronic Microscopy ◽

Electronic Microscopy ◽

X Ray ◽

Uniformity Coefficient ◽

Microstructure And Mechanical Properties ◽

Second Phases

In order to investigate the ratio of Zn/Y on as-cast Mg-4Zn-xY (x=1, 2, 3 in wt. %), microstructure and mechanical properties are analyzed by scanning electronic microscopy (SEM), X-ray diffraction (XRD), energy dispersive spectrum (EDS) and tensile testing. The results indicate that with the decrease of the ratio of Zn/Y, microstructures are refined more greatly and the spheroidization and uniformity coefficient are improved obviously, and the morphologies of second phases are changed from diversity to unity, resulting in an improvement of mechanical properties of alloys.

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Influence of Temperature on Characteristics of TiAl Plasma Surface Niobiumizing

Key Engineering Materials - Progresses in Fracture and Strength of Materials and Structures ◽

10.4028/0-87849-456-1.1854 ◽

2007 ◽

pp. 1854-1857

Author(s):

Xiao Ping Liu ◽

Wen Huai Tian ◽

Chao Li Guo ◽

Dong Dong Chen ◽

Zhi Yong He ◽

...

Keyword(s):

Influence Of Temperature ◽

Plasma Surface ◽

Influence Of Temperature On

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Surface Properties of Dental Nanocomposites After Finishing WithRigid Rotary Instruments

Operative Dentistry ◽

10.2341/12-214-l ◽

2013 ◽

Vol 38 (5) ◽

pp. 519-527 ◽

Cited By ~ 1

Author(s):

SM Marchan ◽

D White ◽

QM Marchan ◽

V Dhuru ◽

WA Smith

Keyword(s):

Surface Roughness ◽

Surface Characteristics ◽

Qualitative Assessment ◽

Scanning Electronic Microscopy ◽

Electronic Microscopy ◽

Control Groups ◽

Average Roughness ◽

Rotary Instruments ◽

Finished Surface ◽

Post Hoc

SUMMARY This study evaluated the surface characteristics of three nanoparticle resin composites (Z350, Heritage 7 Nanohybrid, and Ice) using profilometry and scanning electronic microscopy (SEM) after subjecting them to sequential finishing procedures using rigid rotary instruments. Fifteen 8 mm × 8 mm × 2 mm specimens were fabricated for each tested composite and subjected to one of the following finishing regimens: finishing with green stones followed by white stones, finishing with 45-μm diamond followed by 15-μm diamond, finishing with a 12-fluted carbide followed by a 20-fluted carbide. After finishing, the surfaces were subjected to profilometric testing. Eight parallel tracings were used to scan the finished surface of each specimen. For each recorded profile, the average roughness (Ra) and extreme value descriptor (Rmax) were recorded. On completion of the profilometric testing, two specimens from each group were randomly selected for qualitative assessment by SEM. Profilometric data was analyzed using a one-way analysis of variance and post hoc Scheffe tests. The results demonstrated that the three control groups of the tested nanocomposites behaved as a coherent group with respect to surface roughness. With the exception of the nanohybrid Heritage 7 finished with the carbide instruments, all composites showed an increase in surface roughness. The Z350 and Ice finished with the carbide finishing instruments showed no statistically significant increase in Ra, but both of these composites showed significantly rougher surfaces when finished with diamonds compared with controls. The nanohybrids Ice and Heritage 7 demonstrated significantly higher roughness in terms of Rmax when finished with stones. The SEM correlated well with roughness measurements. The conclusion may be drawn that diamonds and stones produce unacceptable surfaces in terms of roughness on the tested nanocomposites whereas finishing carbides produce acceptable surfaces.

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Influence of Standard Load Micro- and Nanopatterned in Surface Roughness of bleached Teeth and submitted to Different Surface Treatments

The Journal of Contemporary Dental Practice ◽

10.5005/jp-journals-10024-1655 ◽

2015 ◽

Vol 16 (3) ◽

pp. 167-171

Author(s):

Mateus Rodrigues Tonetto ◽

Mônica Barros Silva ◽

André Afif Elossais ◽

Matheus Coelho Bandeca ◽

Shilpa H Bhandi ◽

...

Keyword(s):

Surface Roughness ◽

Surface Texture ◽

Artificial Saliva ◽

Dental Enamel ◽

Surface Treatments ◽

Control Group ◽

Scanning Electronic Microscopy ◽

Electronic Microscopy ◽

Structural Alterations ◽

Whitening Process

ABSTRACT The aim of this study was evaluate the dental enamel after whitening treatment with Opalescence Boost PF™ 38%, correlating the structural alterations in the surface of the enamel with its respective pH and verify if whitened teeth submitted to different finishing and polishing techniques show similar surface texture to healthy teeth (control group). Sixty premolars were divided in 6 groups (n = 10), which had been immersed in artificial saliva during all the experiment. Protocol whitening was performed according to the manufacturer recommendations, and then the specimens were submitted to different polishing technique with Sof-Lex Pop On™ disks, Flex Diamond™ felt disks using two different micrometric polishing pastes (Enamelize™ and Diamond Polish™) and two nanometric polishing pastes (Lummina-E Diamond and Lummina-E Alumina), according to the groups. Representative specimens were analyzed in scanning electronic microscopy (SEM). Whitening gel used in this experiment had modified the morphologic aspect of the enamel surface. It was found that two nanometric polishing pastes (G5 and G6) promoted a less rough surface compared to control group even after the whitening process. How to cite this article do Amaral Nacanichi R, Tonetto MR, Bandéca MC, Andrade MF, Segalla JCM, Silva MB, Bhandi SH, Pedro FLM, Elossais AA. Influence of Standard Load Microand Nanopatterned in Surface Roughness of bleached Teeth and submitted to Different Surface Treatments. J Contemp Dent Pract 2015;16(3):167-171.

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The effect of temperature on high-resolution TEM image contrast

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100139573 ◽

1995 ◽

Vol 53 ◽

pp. 640-641

Author(s):

T. Geipel ◽

W. Mader ◽

P. Pirouz

Keyword(s):

Form Factor ◽

Inelastic Scattering ◽

Accurate Method ◽

Waller Factor ◽

Effect Of Temperature ◽

Specimen Thickness ◽

Influence Of Temperature ◽

Debye Waller Factor ◽

Influence Of Temperature On ◽

Atomic Form Factor

Temperature affects both elastic and inelastic scattering of electrons in a crystal. The Debye-Waller factor, B, describes the influence of temperature on the elastic scattering of electrons, whereas the imaginary part of the (complex) atomic form factor, fc = fr + ifi, describes the influence of temperature on the inelastic scattering of electrons (i.e. absorption). In HRTEM simulations, two possible ways to include absorption are: (i) an approximate method in which absorption is described by a phenomenological constant, μ, i.e. fi; - μfr, with the real part of the atomic form factor, fr, obtained from Hartree-Fock calculations, (ii) a more accurate method in which the absorptive components, fi of the atomic form factor are explicitly calculated. In this contribution, the inclusion of both the Debye-Waller factor and absorption on HRTEM images of a (Oll)-oriented GaAs crystal are presented (using the EMS software.Fig. 1 shows the the amplitudes and phases of the dominant 111 beams as a function of the specimen thickness, t, for the cases when μ = 0 (i.e. no absorption, solid line) and μ = 0.1 (with absorption, dashed line).

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