High-Temperature Isothermal Internal Friction Measurements in NiCoCrAlY Alloys

A new high temperature mechanical spectrometer, based on an inverted torsion pendulum, has been constructed for the measurement of the internal friction and the dynamic shear elastic modulus in two different working modes: (a) as a function of temperature (300 – 1800 K) at imposed frequency, during heating or cooling; and (b) as a function of frequency (10-3 – 10 Hz) in isothermal conditions. The whole installation is computer controlled by a dedicated software specifically developed. We describe the different parts of this new installation, as well as its performances in both temperature and frequency through an original example study on a high temperature structural intermetallic of Fe-Al.

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High Temperature Mechanical Properties of Ti(C, N)-Mo2C-Ni Cermets Studied by Internal Friction Measurements

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:19968161 ◽

1996 ◽

Vol 06 (C8) ◽

pp. C8-743-C8-746 ◽

Cited By ~ 5

Author(s):

T. Viatte ◽

T. Cutard ◽

G. Feusier ◽

W. Benoit

Keyword(s):

Mechanical Properties ◽

High Temperature ◽

Internal Friction ◽

High Temperature Mechanical Properties ◽

Friction Measurements

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Mechanical Spectroscopy Of Equal-Channel Angular Pressed Fe-Cr Alloys And Tungsten

Archives of Metallurgy and Materials ◽

10.1515/amm-2015-0355 ◽

2015 ◽

Vol 60 (3) ◽

pp. 2101-2106 ◽

Cited By ~ 1

Author(s):

Ting Hao ◽

Haiyin Tang ◽

Weibin Jiang ◽

Xianping Wang ◽

Qianfeng Fang

Keyword(s):

High Temperature ◽

Internal Friction ◽

Grain Boundary ◽

Microstructural Stability ◽

Mechanical Spectroscopy ◽

Internal Friction Peak ◽

Static Recovery ◽

Microstructural Transition ◽

Deformed State ◽

Friction Measurements

Abstract Internal friction technique was used to investigate the microstructural stability of equal-channel angular pressed (ECAP) 9Cr1Mo steel (T91), Fe-18wt.%Cr alloy, and pure W. Several non-relaxation internal friction peaks are observed in three ECAP-strained specimens, which are related to the microstructural transition from a severely deformed state to a static recovery state of dislocations, and to recrystallized state. Along with the disappearance of the P1 peak, another relaxation internal friction peak P2 is observed during the second heating run only in Fe-18wt.%Cr alloy, and it does not disappear even during subsequent third heating run. This peak is not observed in T91 steel and W. The P2 peak is likely associated with a process of grain boundary (GB) sliding. Unlike T91, no abundant carbide precipitates distribute on GBs to pin GB and repulse GB sliding, thus, the P2 peak only occurs in Fe-18wt.%Cr alloy. It is concluded that high-temperature internal friction measurements are required to detect the grain boundary peak in pure W.

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High Temperature Internal Friction Measurements in γ'-Ni3Al

Materials Science Forum ◽

10.4028/www.scientific.net/msf.119-121.397 ◽

1993 ◽

Vol 119-121 ◽

pp. 397-400 ◽

Cited By ~ 10

Author(s):

P. Gadaud ◽

K. Chakib

Keyword(s):

High Temperature ◽

Internal Friction ◽

Friction Measurements

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Internal Friction of a High-Nb Gamma-TiAl-Based Alloy with Different Microstructures

MRS Proceedings ◽

10.1557/proc-842-s7.13 ◽

2004 ◽

Vol 842 ◽

Author(s):

M. Weller ◽

H. Clemens ◽

G. Dehm ◽

G. Haneczok ◽

S. Bystrzanowski ◽

...

Keyword(s):

Electron Microscopy ◽

High Temperature ◽

Internal Friction ◽

Volume Diffusion ◽

Loss Peak ◽

Self Diffusion ◽

Transmission Electron ◽

Diffusion Controlled ◽

Friction Measurements ◽

Fully Lamellar

ABSTRACTAn intermetallic Ti-46Al-9Nb (at%) alloy with different microstructures (near gamma, duplex, and fully lamellar) was studied by internal friction measurements at 300 K to 1280 K using different frequency ranges: (I) 0.01 Hz to 10 Hz and (II) around 2 kHz. The loss spectra in range I show (i) a loss peak of Debye type at T ≈ 1000 K which is only present in duplex and fully lamellar samples; (ii) a high-temperature damping background above ≈ 1100 K. The activation enthalpies determined from the frequency shift are H = 2.9 eV for the loss peak and H = 4.1–4.3 eV for the high-temperature damping background. The activation enthalpies for the visco-elastic high-temperature damping background agree well with values obtained from creep experiments and are in the range of those determined for self-diffusion of Al in TiAl. These results indicate that both properties (high-temperature damping background and creep) are controlled by volume diffusion-assisted climb of dislocations. The loss peak is assigned to diffusion-controlled local glide of dislocation segments which, as indicated by transmission electron microscopy observations, are pinned at lamella interfaces.

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