Effect of H-Doping on Damping Capacity of Various NiTi-Based Alloys at kHz Frequencies

2006 ◽  
Vol 128 (3) ◽  
pp. 254-259 ◽  
Author(s):  
B. Coluzzi ◽  
A. Biscarini ◽  
G. Mazzolai ◽  
F. M. Mazzolai ◽  
A. Tuissi
Keyword(s):  
Internal Friction ◽  
Twin Boundary ◽  
Room Temperature ◽  
Mechanical Energy ◽  
Noise Pollution ◽  
Metal Alloy ◽  
Maximum Efficiency ◽  
Damping Capacity ◽  
Good Opportunity ◽  
Hydrogen Doping

The internal friction Q−1 and the Young’s modulus E of NiTi based alloys have been measured as a function of temperature after various thermomechanical and hydrogen-doping treatments given to the materials. Hydrogen is found to play a major role introducing tall damping peaks associated with Snoek-type and H-twin boundary relaxations. Levels of Q−1 as high as 0.08 have been detected, which are among the highest to date measured in metal alloy systems. For appropriate alloy compositions, these peaks occur at around room temperature (for acoustical frequencies), thus providing a good opportunity to reduce machinery vibrations and noise pollution. In the paper, the conditions are highlighted under which maximum efficiency can be reached in the conversion of mechanical energy into heat.

Damping Properties of Vacuum Annealed and H-Doped NiTi Based Alloys at Low Stress Amplitudes

2006 ◽  
Vol 319 ◽  
pp. 1-8 ◽  
Author(s):  
B. Coluzzi ◽  
A. Biscarini ◽  
Giovanni Mazzolai ◽  
Fabio M. Mazzolai ◽  
Ausonio Tuissi ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Internal Friction ◽  
Young’S Modulus ◽  
Twin Boundary ◽  
Room Temperature ◽  
Maximum Height ◽  
Damping Properties ◽  
Transient Effects ◽  
Scanning Calorimetry ◽  
Hydrogen Doping

The internal friction (IF) and the Young’s modulus (E) of NiTi based alloys have been investigated at 1 Hz and 1 kHz frequencies after various sequences of thermo-mechanical treatments and hydrogen-doping given to the materials. Differential scanning calorimetry (DSC) has also been used as a complementary investigation tool. Apart from the transient effects, only occurring at 1 Hz frequencies, the data indicate a substantial insensitivity of damping to frequency. The results show that the H-Snoek and the H-twin boundary relaxations get their maximum height for H contents nH (nH=H/Me) equal to about 0.025 and 0.008, respectively. At kHz frequencies the IF peaks associated with these relaxations occur at around room temperature in the Ni49Ti51 and Ni30Ti50Cu20 alloys. Thus, these appear to be the most promising materials for applications aimed at the reduction of vibrations.

Effect of Isothermal Ageing on Damping Capacity of Cu-20.4Al-8.7Mn

2012 ◽  
Vol 268-270 ◽  
pp. 312-315
Author(s):  
Gang Ling Hao ◽  
Qiao Ping Xu ◽  
Wei Guo Wang
Keyword(s):  
Internal Friction ◽  
Room Temperature ◽  
Ageing Temperature ◽  
Damping Capacity ◽  
Temperature Ageing ◽  
Changing Trend ◽  
Higher Temperature ◽  
Friction Measurements ◽  
Isothermal Ageing ◽  
Lower Temperature

The effect of ageing temperature on damping capacity of the Cu-20.4Al-8.7Mn alloy at room temperature was investigated by internal friction measurements. The results indicated that damping capacity of the alloy exhibits a non-monotonous changing trend with ageing temperature. Ageing at lower temperature of less than 150oC, damping capacity rapidly increses even up to maximum of 0.01 with the increasing ageing temperature, the reason of which should relate with the increased amount of twin boundaries and phase interfaces between martensites due to the thinning and splitting of martensitic plates, whereas when the ageing temperature exceeds 150oC, the damping capacity trends to steeply decrease as the ageing temperature increases until close to a constant in last corresponding to the ageing at higher temperature due to the occurrence and complete finish of transformation of martensites to austenites.

Change in damping capacity arising from twin-boundary segregation in solid-solution magnesium alloys

2020 ◽  
Vol 100 (10) ◽  
pp. 494-505
Author(s):  
Hidetoshi Somekawa ◽  
Dudekula Althaf Basha ◽  
Alok Singh ◽  
Tomohito Tsuru ◽  
Hiroyuki Watanabe
Keyword(s):  
Solid Solution ◽  
Twin Boundary ◽  
Magnesium Alloys ◽  
Boundary Segregation ◽  
Damping Capacity

Effects of Macroscopic Pores on the Damping Behaviors of Metal Materials

2011 ◽  
Vol 66-68 ◽  
pp. 1155-1162
Author(s):  
Jian Ning Wei ◽  
Gen Mei Li ◽  
Li Ling Zhou ◽  
Xue Yun Zhou ◽  
Jian Min Yu ◽  
...  
Keyword(s):  
Internal Friction ◽  
Pure Aluminum ◽  
Air Pressure ◽  
Damping Capacity ◽  
Infiltration Process ◽  
Pressure Infiltration ◽  
Temperature Range ◽  
Commercially Pure ◽  
Damping Behavior ◽  
Metal Materials

A large number of macroscopic pores were introduced into commercially pure aluminum (Al) and Zn-Al eutectoid alloy by air pressure infiltration process to comparatively study the influence of macroscopic pores on the damping behaviors of the materials. Macroscopic pores size are on the order of a millimetre (0.5~1.4mm) and in large proportions, typically high 76vol.%. The damping behavior of the materials is characterized by internal friction (IF). The IF was measured on a multifunction internal friction apparatus (MFIFA) at frequencies of 0.5, 1.0 and 3.0 Hz over the temperature range of 25 to 400 °C, while continuously changing temperature. The damping capacity of the metal materials is shown to increase with introducing macroscopic pores. Finally, the operative damping mechanisms in the metal materials with macroscopic pores were discussed in light of IF measurements.

Effect of cooling rate on damping capacity of Fe–Cr based ferromagnetic metal alloy

2016 ◽  
Vol 650 ◽  
pp. 382-388 ◽  
Author(s):  
Hui Wang ◽  
Fu Wang ◽  
Jun Xiao ◽  
Yuan Wang ◽  
Ce Ma ◽  
...  
Keyword(s):  
Cooling Rate ◽  
Ferromagnetic Metal ◽  
Metal Alloy ◽  
Damping Capacity

Effect of Heat Treatments on the Damping Characteristics of TiNi-Based Shape Memory Alloys

2006 ◽  
Vol 319 ◽  
pp. 33-38 ◽  
Author(s):  
I. Yoshida ◽  
Kazuhiro Otsuka
Keyword(s):  
Internal Friction ◽  
Shape Memory Alloys ◽  
Shape Memory ◽  
Low Frequency ◽  
Heat Treatments ◽  
Damping Capacity ◽  
Temperature Hysteresis ◽  
Temperature Spectrum ◽  
Two Peaks ◽  
Very High

Low frequency internal friction of Ti49Ni51 binary and Ti50Ni40Cu10 ternary shape memory alloys has been measured. The effect of solution and aging heat treatments on the damping property was examined. The temperature spectrum of internal friction for TiNi binary alloy consists, in general, of two peaks; one is a transition peak which is associated with the parent-martensite transformation and is rather unstable in a sense that it strongly depends on the frequency and decreases considerably when held at a constant temperature. The other one is a very high peak of the order of 10-2, which appears at around 200K. It appears both on cooling and on heating with no temperature hysteresis, and is very stable. The behavior of the peak is strongly influenced by the heat treatments. The trial of two-stage aging with a purpose of improving the damping capacity has been proved unsatisfactory. TiNiCu has a very high damping, the highest internal friction reaching 0.2, but by quenching from very high temperature, say 1373K, the damping is remarkably lowered. For the realization of high damping the quenching from a certain temperature range around 1173K seems the most preferable condition.

Search for High Damping Metallic Glasses

2006 ◽  
Vol 319 ◽  
pp. 151-156 ◽  
Author(s):  
Y. Hiki ◽  
M. Tanahashi ◽  
Shin Takeuchi
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Internal Friction ◽  
Metallic Glass ◽  
Room Temperature ◽  
Temperature Stability ◽  
Temperature Peak ◽  
High Temperature Side ◽  
Side Slope ◽  
Temperature Side

In a hydrogen-doped metallic glass, there appear low-temperature and high-temperature internal friction peaks respectively associated with a point-defect relaxation and the crystallization. The high-temperature-side slope of low-temperature peak and also the low-temperature-side slope of high-temperature peak enhance the background internal friction near the room temperature. A hydrogen-doped Mg-base metallic glass was proposed as a high-damping material to be used near and somewhat above the room temperature. Stability of the high damping was also checked.

scholarly journals Room temperature giant magnetostriction in single-crystal nickel nanowires

2019 ◽  
Vol 11 (1) ◽  
Author(s):  
Anastasios Pateras ◽  
Ross Harder ◽  
Sohini Manna ◽  
Boris Kiefer ◽  
Richard L. Sandberg ◽  
...  
Keyword(s):  
Magnetic Field ◽  
External Magnetic Field ◽  
Single Crystal ◽  
Room Temperature ◽  
Magnetic Energy ◽  
Mechanical Energy ◽  
Three Dimensional ◽  
Local Strain ◽  
Nickel Nanowires ◽  
Giant Magnetostriction

Abstract Magnetostriction is the emergence of a mechanical deformation induced by an external magnetic field. The conversion of magnetic energy into mechanical energy via magnetostriction at the nanoscale is the basis of many electromechanical systems such as sensors, transducers, actuators, and energy harvesters. However, cryogenic temperatures and large magnetic fields are often required to drive the magnetostriction in such systems, rendering this approach energetically inefficient and impractical for room-temperature device applications. Here, we report the experimental observation of giant magnetostriction in single-crystal nickel nanowires at room temperature. We determined the average values of the magnetostrictive constants of a Ni nanowire from the shifts of the measured diffraction patterns using the 002 and 111 Bragg reflections. At an applied magnetic field of 600 Oe, the magnetostrictive constants have values of λ100 = −0.161% and λ111 = −0.067%, two orders of magnitude larger than those in bulk nickel. Using Bragg coherent diffraction imaging (BCDI), we obtained the three-dimensional strain distribution inside the Ni nanowire, revealing nucleation of local strain fields at two different values of the external magnetic field. Our analysis indicates that the enhancement of the magnetostriction coefficients is mainly due to the increases in the shape, surface-induced, and stress-induced anisotropies, which facilitate magnetization along the nanowire axis and increase the total magnetoelastic energy of the system.

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