Thermal stability of Ti–45 wt % Nb alloy at isothermal annealing

2020 ◽  
Author(s):  
I. A. Glukhov ◽  
A. Yu. Eroshenko ◽  
M. A. Khimich ◽  
A. M. Mairambekova ◽  
A. I. Tolmachev ◽  
...  
2007 ◽  
Vol 43 (24) ◽  
pp. 1341 ◽  
Author(s):  
R. Joseph ◽  
N.K. Viswanathan ◽  
S. Asokan ◽  
K.V. Madhav ◽  
B. Srinivasan

Author(s):  
H.G. Jiang ◽  
M.L. Lau ◽  
E.J. Lavernia

Abstract Nanocrystalline Inconel 718 and Ni powders were prepared using two approaches: methanol and cryogenic attritor milling. High velocity oxy-fuel (HVOF) spraying of milled Inconel 718 powders was then utilized to produce Inconel 718 coatings with a nanocrystalline grain size. Isothermal heat treatments were carried out to study the thermal stability of the methanol milled and cryomilled Inconel 718 powders, as well as the HVOF Inconel 718 coatings. All nanocrystalline Inconel 718 powders and coatings studied herein exhibited significant thermal stability against grain growth as evidenced by a grain size around 100 nm following annealing at 1273 K for 60 min. In the case of the cryomilled nanocrystalline Ni powders, isothermal grain growth behavior was studied, from which the parameters required for the prediction of the microstructural evolution during a non-isothermal annealing were acquired. The theoretical simulation of grain growth behavior of nanocrystalline Ni during non-isothermal annealing conditions yields results that are in good correspondence with the experimental results.


1981 ◽  
Vol 12 ◽  
Author(s):  
R. H. van de Merwe ◽  
R. W. Smith

ABSTRACTVarious thermal treatments have been applied to Cd-Zn and Pb-Cd eutectic alloys in an attempt to better understand the thermal stability of eutectics close to their melting temperatures. Specimens of each system were grown at 40, 400 and 4000 mm/hr to obtain microstructures which were either lamellar, lamellar/cellular, or cellular. These specimens were thermally treated by either: (1) isothermal annealing at 0.95 Tm (up to 192 hrs), (2) thermal cycling between room temperature and 0.95 Tm (up to 64 cycles), (3) exposing to thermal gradients parallel to the growth direction and maintaining one end of the specimen at 0.95 Tm and the opposite end at room temperature (up to 48 hrs). It was found in all cases that some microstructural changes occurred but that the two alloy systems displayed marked differences in degradation sequence. An explanation and interpretation of these decay sequences is attempted. The mechanical properties of the variouslytreated alloy specimens were determined and are correlated with the observed microstructural features. The Cd-Zn specimens coarsened more rapidly than equivalent Pb-Cd specimens, as might be expected since the interphase boundary energies have been reported as 86 and 67 erg/cm2 respectively.


Author(s):  
Shiro Fujishiro ◽  
Harold L. Gegel

Ordered-alpha titanium alloys having a DO19 type structure have good potential for high temperature (600°C) applications, due to the thermal stability of the ordered phase and the inherent resistance to recrystallization of these alloys. Five different Ti-Al-Ga alloys consisting of equal atomic percents of aluminum and gallium solute additions up to the stoichiometric composition, Ti3(Al, Ga), were used to study the growth kinetics of the ordered phase and the nature of its interface.The alloys were homogenized in the beta region in a vacuum of about 5×10-7 torr, furnace cooled; reheated in air to 50°C below the alpha transus for hot working. The alloys were subsequently acid cleaned, annealed in vacuo, and cold rolled to about. 050 inch prior to additional homogenization


Author(s):  
Yih-Cheng Shih ◽  
E. L. Wilkie

Tungsten silicides (WSix) have been successfully used as the gate materials in self-aligned GaAs metal-semiconductor-field- effect transistors (MESFET). Thermal stability of the WSix/GaAs Schottky contact is of major concern since the n+ implanted source/drain regions must be annealed at high temperatures (∼ 800°C). WSi0.6 was considered the best composition to achieve good device performance due to its low stress and excellent thermal stability of the WSix/GaAs interface. The film adhesion and the uniformity in barrier heights and ideality factors of the WSi0.6 films have been improved by depositing a thin layer of pure W as the first layer on GaAs prior to WSi0.6 deposition. Recently WSi0.1 has been used successfully as the gate material in 1x10 μm GaAs FET's on the GaAs substrates which were sputter-cleaned prior to deposition. These GaAs FET's exhibited uniform threshold voltages across a 51 mm wafer with good film adhesion after annealing at 800°C for 10 min.


1991 ◽  
Vol 1 (12) ◽  
pp. 1823-1836 ◽  
Author(s):  
M. Bessière ◽  
A. Quivy ◽  
S. Lefebvre ◽  
J. Devaud-Rzepski ◽  
Y. Calvayrac

1994 ◽  
Vol 4 (4) ◽  
pp. 653-657
Author(s):  
B. Bonzi ◽  
M. El Khomssi ◽  
H. Lanchon-Ducauquis

1998 ◽  
Vol 08 (PR2) ◽  
pp. Pr2-63-Pr2-66 ◽  
Author(s):  
R. Varga ◽  
P. Vojtaník ◽  
A. Lovas

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