Observation of the Glass Transition of Metallic Glasses by Low-Frequency Internal Friction Measurements with a Collette Pendulum

1993 ◽  
Vol 119-121 ◽  
pp. 535-540 ◽  
Author(s):  
H.R. Sinning
Keyword(s):  
Glass Transition ◽  
Internal Friction ◽  
Metallic Glasses ◽  
Low Frequency ◽  
Friction Measurements

Effect of Purity on Dislocation-Induced Relaxations in Molybdenum Single Crystals

2015 ◽  
Vol 363 ◽  
pp. 106-111
Author(s):  
Shigeru Suzuki ◽  
Alfred Seeger
Keyword(s):  
Internal Friction ◽  
Single Crystals ◽  
High Purity ◽  
Low Frequency ◽  
Activation Process ◽  
Dislocation Interaction ◽  
Dissolved Carbon ◽  
Dislocation Pinning ◽  
Friction Measurements ◽  
Substitutional Impurities

Dislocation-induced relaxations in different molybdenum single crystals were investigated by means of low-frequency internal friction measurements in the temperature range of 20–600 K. The results indicated that the appearance of the dislocation-induced relaxations strongly depends on the purity of the molybdenum, although the intrinsic dislocation relaxations appeared at about 100 K and 450 K in the high-purity molybdenum. The molybdenum containing a small amount of carbon did not exhibit the intrinsic dislocation relaxations but rather revealed a modulus increase due to the dislocation pinning caused by the dissolved carbon. When the molybdenum containing a small amount of carbon was annealed up to 700 K, a new relaxation peak appeared at about 450 K. The activation process for this relaxation indicated that it could be attributed to the relaxation due to a carbon-dislocation interaction. In addition, it was shown that the dislocation-induced relaxations in medium-purity molybdenum were small, which was attributed to the residual substitutional impurities in the molybdenum.

Effects of Fe Addition on the Phase Transformation Internal Friction in Ni-Al-Based Alloys

2021 ◽  
Vol 888 ◽  
pp. 91-95
Author(s):  
Zheng Cun Zhou ◽  
Jie Du ◽  
Su Yi Gu ◽  
Xiao Bin Zhu ◽  
Yi Fei Yang
Keyword(s):  
Phase Transformation ◽  
Internal Friction ◽  
Low Frequency ◽  
Peak Height ◽  
Peak Temperature ◽  
Chemical Compositions ◽  
Fe Content ◽  
Mechanical Spectrum ◽  
Friction Measurements ◽  
Fe Addition

The influences of chemical compositions on the internal friction of phase transformation were investigated for the quenched Ni-Al-based alloys. The internal friction measurements were completed using a low-frequency mechanical spectrum apparatus through forced vibration method. It was shown that the chemical compositions have the great influences on the internal friction of phase transition for the oil-cooled Ni-Al-based alloys. The peak-temperature of internal friction is lowered, and the peak-height is increased and the peak-width is narrowed when Fe content is elevated. The reducing of the peak-temperature is attributed to the increase of stability of γ phase due to the addition of Fe. The changes of the parameters of the peak are also related to the Aleq (equivalent Al) contents.

FLUCTUATION OF INTERNAL FRICTION IN METALLIC GLASSES

2011 ◽  
Vol 1300 ◽  
Author(s):  
Y. Miyauchi ◽  
R. Tamura ◽  
Y. Hiki
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Internal Friction ◽  
Metallic Glass ◽  
Transition Region ◽  
Frequency Spectrum ◽  
Metallic Glasses ◽  
Glass Transition Region ◽  
Characteristic Peak

AbstractInternal friction (IF) of a metallic glass Zr55Cu30Al10Ni5 has been measured near the glass transition temperature Tg (= 666 K). The measurement is performed by using DMA (TA Instrument) apparatus at a frequency of 0.01 Hz for a specimen stabilized by annealing. The specimen is kept at a constant temperature T, and the IF value Q-1 is measured as a function of time t. A fluctuation of Q-1 with time is seen, and the magnitude of the fluctuation, F(t), is derived from the Q-1-vs-t data. F(t) is Fourier transformed to the frequency spectrum F(f). Such experiment and analyses are carried out at various temperatures near Tg. A characteristic peak (f ~ 10-3 Hz) is found in the spectrum F(f) in the glass transition region.

Hydrogen-doped Bulk Metallic Glasses as High Damping Material

2000 ◽  
Vol 644 ◽  
Author(s):  
Teruaki Yagi ◽  
Rikiya Oguro ◽  
Ryuji Tamura ◽  
Shin Takeuchi
Keyword(s):  
Internal Friction ◽  
Metallic Glasses ◽  
Bulk Metallic Glasses ◽  
High Strength ◽  
High Ductility ◽  
Hydrogen Atoms ◽  
High Affinity ◽  
Damping Material ◽  
Friction Measurements ◽  
Peak Value

AbstractBulk metallic glasses have extremely high strength and high ductility and are quite useful as the structural material. Many of bulk metallic glasses are based on Zr, Ti and Pd; these elements have a high affinity with hydrogen and hence the bulk metallic glasses can contain a large amount of hydrogen atoms. It is known that hydrogenized amorphous metals, as well as hydrogenized metallic crystals, exhibit Snoek-type relaxation, and hence metallic glasses containing a high density of hydrogen can have a high internal friction.In the present experiments, internal friction measurements have been performed for bulk metallic glasses doped with a variety of hydrogen concentrations. It is shown that the peak value of the internal friction reaches the order of 10-2 in Zr-based bulk metallic glasses which have the fracture strength as high as 1.5 GPa. Thus, hydrogen-doped bulk metallic glasses can be used as the high-strength, high-damping material.

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