The Effect of Thermal Hydrogenation Processing on the Nano-Size Grain Refinement and Oxide Layer Fomation of Ti-6Al-4V Alloy

There are investigated the structural properties of 64Zn+ ion-beam induced nano-size voids in as implanted and subsequent furnace annealing SiOSuperscript text2/Si(100) substrates. Then 64Zn+ ions with energy of E=100keV were implanted into SiO2 layer to a fluence of D=2×1014cm-2. After this furnace thermal annealing at temperature 400°C during 1h in neutral (nitrogen) atmosthere was made. It is revealed, that in as-implanted sample the surface is non-uniform and there is some structurization of a SiO2 layer. In this state, metal Zn NPs an order of ten nm in diameter are formed in the depth region around the projected range. There is thus a net flux of Zn out of the nanoparticles (NPs) into an oxide layer closer to the surface. As Zn has a big diffusion constant and a high vaper pressure there are occured out-diffusion of Zn from a SiO2 surface layer. The volume occupied by the Zn NPs becomes a void. It results to formation of cavities, which combining among themselves, form voids.

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Grain Refinement in Titanium-Erbium Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052626 ◽

1974 ◽

Vol 32 ◽

pp. 522-523

Author(s):

B. B. Rath ◽

J. E. O'Neal ◽

R. J. Lederich

Keyword(s):

Electron Microscopy ◽

Size Distribution ◽

Grain Refinement ◽

Grain Growth ◽

Volume Fraction ◽

Pure Titanium ◽

Systematic Investigation ◽

Second Phase ◽

Titanium Matrix ◽

Average Size

Addition of small amounts of erbium has a profound effect on recrystallization and grain growth in titanium. Erbium, because of its negligible solubility in titanium, precipitates in the titanium matrix as a finely dispersed second phase. The presence of this phase, depending on its average size, distribution, and volume fraction in titanium, strongly inhibits the migration of grain boundaries during recrystallization and grain growth, and thus produces ultimate grains of sub-micrometer dimensions. A systematic investigation has been conducted to study the isothermal grain growth in electrolytically pure titanium and titanium-erbium alloys (Er concentration ranging from 0-0.3 at.%) over the temperature range of 450 to 850°C by electron microscopy.

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Structural changes in silicon-on-insulator material during post-implantation annealing

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100145054 ◽

1986 ◽

Vol 44 ◽

pp. 736-737

Author(s):

C. O. Jung ◽

S. J. Krause ◽

S.R. Wilson

Keyword(s):

Integrated Circuits ◽

Oxide Layer ◽

High Speed ◽

Structural Changes ◽

Device Fabrication ◽

Silicon On Insulator ◽

High Quality ◽

Radiation Hardened ◽

Post Implantation ◽

Very High

Silicon-on-insulator (SOI) structures have excellent potential for future use in radiation hardened and high speed integrated circuits. For device fabrication in SOI material a high quality superficial Si layer above a buried oxide layer is required. Recently, Celler et al. reported that post-implantation annealing of oxygen implanted SOI at very high temperatures would eliminate virtually all defects and precipiates in the superficial Si layer. In this work we are reporting on the effect of three different post implantation annealing cycles on the structure of oxygen implanted SOI samples which were implanted under the same conditions.

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TEM investigations of surface residual stress relaxation in A12O3 and Al2O3-SiC nanocomposite

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100170876 ◽

1994 ◽

Vol 52 ◽

pp. 628-629

Author(s):

J. Fang ◽

H. M. Chan ◽

M. P. Harmer

Keyword(s):

Residual Stress ◽

Single Phase ◽

Stress Relief ◽

Stress Recovery ◽

Surface Residual Stress ◽

Microscopic Mechanism ◽

Sic Particles ◽

Annealing Procedure ◽

The Difference ◽

Nano Size

It was Niihara et al. who first discovered that the fracture strength of Al2O3 can be increased by incorporating as little as 5 vol.% of nano-size SiC particles (>1000 MPa), and that the strength would be improved further by a simple annealing procedure (>1500 MPa). This discovery has stimulated intense interest on Al2O3/SiC nanocomposites. Recent indentation studies by Fang et al. have shown that residual stress relief was more difficult in the nanocomposite than in pure Al2O3. In the present work, TEM was employed to investigate the microscopic mechanism(s) for the difference in the residual stress recovery in these two materials.Bulk samples of hot-pressed single phase Al2O3, and Al2O3 containing 5 vol.% 0.15 μm SiC particles were simultaneously polished with 15 μm diamond compound. Each sample was cut into two pieces, one of which was subsequently annealed at 1300° for 2 hours in flowing argon. Disks of 3 mm in diameter were cut from bulk samples.

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