Grain boundary internal friction measurements of NiCrCe alloys

AbstractInternal friction measurements have been performed on Ni-20 wt% Cr alloys containing trace additions of Ce ranging from 0 to 180 at ppm, in order to determine grain boundary sliding kinetics and associated stress relaxation phenomena. Two anelastic relaxation peaks have been observed corresponding to intrinsic grain boundary sliding between carbide precipitates and to macroscopic sliding with elastic accommodation at triple points. The effects of Ce on these grain boundary phenomena and resulting alloy ductilities are also presented.

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Characterization of Thin Films by Internal Friction Measurements

MRS Proceedings ◽

10.1557/proc-239-215 ◽

1991 ◽

Vol 239 ◽

Cited By ~ 6

Author(s):

H. G. Bohn ◽

C. M. Su

Keyword(s):

Internal Friction ◽

Grain Boundary ◽

Boundary Diffusion ◽

Grain Boundary Diffusion ◽

Al Alloy ◽

Alloy Films ◽

Boundary Relaxation ◽

Friction Measurements ◽

Influence Of Impurities

ABSTRACT: Internal friction has been employed to characterize various properties of thin Al and Al-alloy films. The grain boundary relaxation peak was useda) to determine the activation energies for grain boundary diffusion in the alloy films,b) to investigate the influence of impurities on the grain boundary diffusion in Al at concentration levels as low as 300 ppm, andc) to get information about the adhesion strength between the film and the substrate.

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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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