Viscoelastic Vibration Damping Materials for Application in a Temperature Range above 150°C

2017 ◽  
Vol 730 ◽  
pp. 569-573 ◽  
Author(s):  
Wen Fei Wang ◽  
Xin Zhi Lin ◽  
Yu Liang Ma

We demonstrate a new type of viscoelastic vibration damping material with high damping performances (tan δ=E′/E′′ ≥0.3 where E′ and E′′ are the storage and loss Young’s moduli, respectively) at a high temperature range between 200°C and 250°C utilizing a special polymer resin of higher glass transition temperature corresponding to the application temperature range and larger pendant groups offering higher efficiency of the energy dissipation. In addition, the damping property of the bulk material reinforced with glass fiber will be significantly improved, where the peak tan δ value can reach 0.7. In this paper, we put the emphasis on the preparation process and properties characterization of this new type material, and try to provide a new method to fabricate a viscoelastic damping material (VDM) usable for applications in the field of high temperature vibration reduction, in contrast to the conventional ones whose damping properties will dramatically decay once the ambient temperature is above 100°C.

2021 ◽  
Vol 2 (396) ◽  
pp. 67-72
Author(s):  
A. Bagerman ◽  
◽  
A. Troitsky ◽  
I. Leonova ◽  
◽  
...  

Object and purpose of research. The object is steels and alloys for high-temperature applications. The purpose of the study is to obtain the necessary data for predicting the Young’s modulus of steels and alloys before their full-scale tests. Materials and methods. The data on the Young’s modulus of pure metals and reference data on the Young’s modulus of steels and alloys for high-temperature applications are the materials used in this study. The study uses the concept of "constraint" parameter to rank steels and alloys. Main results. The Young’s moduli of iron and nickel were determined during their operation as a part of steels and alloys, an algorithm for the predictive assessment of the Young’s modulus of steels and alloys was compiled in the temperature range 20–800 °С. Conclusion. It is shown that in the absence of experimental data, the Young’s modulus of steels and alloys can be estimated by the value of the "available" Young’s modulus, determined by the value of the Young’s modulus of pure metals. The results of the study showed the possibility of changing the Young’s modulus of pure metals during their operation as a part of steels and alloys, the characteristics of the Young’s modulus of iron and nickel during their operation as a part of steels and alloys and the algorithm for predicting the Young’s modulus of steels and alloys based on these metals in the temperature range of 20–800 °C were obtained.


2010 ◽  
Vol 160-162 ◽  
pp. 1498-1502
Author(s):  
Xiang Zhang ◽  
Qi Wei He ◽  
Shao Chun Ding

In aerospace field and submarine field, structure vibration is ubiquity and the work environments is very bad which is oily and work temperature is high. Damping material is a kind of high molecular polymer which has elastic solid property and viscous fluid property at the same time and can attenuate bending vibration of structures and reduce radiated noise. So using damping material to control the structures vibration is an effective method. By experimentations and performance testing of 200 formulas, a new kind of excellent damping material has been successfully developed which is oil resistance and high temperature resistance. At the same time, the paper has established the formula database of damping materials which is a good base for many different engineering applications of damping material with oil resistance and high temperature resistance.


Author(s):  
N. Rozhanski ◽  
A. Barg

Amorphous Ni-Nb alloys are of potential interest as diffusion barriers for high temperature metallization for VLSI. In the present work amorphous Ni-Nb films were sputter deposited on Si(100) and their interaction with a substrate was studied in the temperature range (200-700)°C. The crystallization of films was observed on the plan-view specimens heated in-situ in Philips-400ST microscope. Cross-sectional objects were prepared to study the structure of interfaces.The crystallization temperature of Ni5 0 Ni5 0 and Ni8 0 Nb2 0 films was found to be equal to 675°C and 525°C correspondingly. The crystallization of Ni5 0 Ni5 0 films is followed by the formation of Ni6Nb7 and Ni3Nb nucleus. Ni8 0Nb2 0 films crystallise with the formation of Ni and Ni3Nb crystals. No interaction of both films with Si substrate was observed on plan-view specimens up to 700°C, that is due to the barrier action of the native SiO2 layer.


Alloy Digest ◽  
1967 ◽  
Vol 16 (10) ◽  

Abstract NICKELVAC L-605 is a double vacuum melted, cobalt-base alloy for high temperature applications. It is recommended for highly stressed parts operating in the temperature range of 1700 to 2000 F. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as creep and fatigue. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Co-53. Producer or source: Allvac Metals Company, A Teledyne Company.


1995 ◽  
Author(s):  
Shoko Yoshikawa ◽  
R. Meyer ◽  
J. Witham ◽  
S. Y. Agadda ◽  
G. Lesieutre

2020 ◽  
Vol 12 ◽  
Author(s):  
Fang Wang ◽  
Jingkai Wei ◽  
Caixia Guo ◽  
Tao Ma ◽  
Linqing Zhang ◽  
...  

Background: At present, the main problems of Micro-Electro-Mechanical Systems (MEMS) temperature detector focus on the narrow range of temperature detection, difficulty of the high temperature measurement. Besides, MEMS devices have different response characteristics for various surrounding temperature in the petrochemical and metallurgy application fields with high-temperature and harsh conditions. To evaluate the performance stability of the hightemperature MEMS devices, the real-time temperature measurement is necessary. Objective: A schottky temperature detector based on the metal/n-ZnO/n-Si structures is designed to measure high temperature (523~873K) for the high-temperature MEMS devices with large temperature range. Method: By using the finite element method (FEM), three different work function metals (Cu, Ni and Pt) contact with the n-ZnO are investigated to realize Schottky. At room temperature (298K) and high temperature (523~873K), the current densities with various bias voltages (J-V) are studied. Results: The simulation results show that the high temperature response power consumption of three schottky detectors of Cu, Ni and Pt decreases successively, which are 1.16 mW, 63.63 μW and 0.14 μW. The response temperature sensitivities of 6.35 μA/K, 0.78 μA/K, and 2.29 nA/K are achieved. Conclusion: The Cu/n-ZnO/n-Si schottky structure could be used as a high temperature detector (523~873K) for the hightemperature MEMS devices. It has a large temperature range (350K) and a high response sensitivity is 6.35 μA/K. Compared with traditional devices, the Cu/n-ZnO/n-Si Schottky structure based temperature detector has a low energy consumption of 1.16 mW, which has potential applications in the high-temperature measurement of the MEMS devices.


Metals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 581
Author(s):  
Abdulhakim A. Almajid

This study is focused on the deformation mechanism and behavior of naturally aged 7010 aluminum alloy at elevated temperatures. The specimens were naturally aged for 60 days to reach a saturated hardness state. High-temperature tensile tests for the naturally aged sample were conducted at different temperatures of 573, 623, 673, and 723 K at various strain rates ranging from 5 × 10−5 to 10−2 s−1. The dependency of stress on the strain rate showed a stress exponent, n, of ~6.5 for the low two temperatures and ~4.5 for the high two temperatures. The apparent activation energies of 290 and 165 kJ/mol are observed at the low, and high-temperature range, respectively. These values of activation energies are greater than those of solute/solvent self-diffusion. The stress exponents, n, and activation energy observed are rather high and this indicates the presence of threshold stress. This behavior occurred as a result of the dislocation interaction with the second phase particles that are existed in the alloy at the testing temperatures. The threshold stress decreases in an exponential manner as temperature increases. The true activation energy was computed by incorporating the threshold stress in the power-law relation between the stress and the strain. The magnitude of the true activation energy, Qt dropped to 234 and 102 kJ/mol at the low and high-temperature range, respectively. These values are close to that of diffusion of Zinc in Aluminum and diffusion of Magnesium in Aluminum, respectively. The Zener–Hollomon parameter for the alloy was developed as a function of effective stress. The data in each region (low and high-temperature region) coalescence in a segment line in each region.


Author(s):  
Yiqin Zhang ◽  
Honglei Mu ◽  
Haiyan Gao ◽  
Hangjun Chen ◽  
Weijie Wu ◽  
...  

CrystEngComm ◽  
2020 ◽  
Vol 22 (44) ◽  
pp. 7601-7606
Author(s):  
Chunxiao Wang ◽  
Hong-an Ma ◽  
Liangchao Chen ◽  
Xinyuan Miao ◽  
Liang Zhao ◽  
...  

Here, a new type of supercharged cell assembly is proposed that can effectively reduce the oil pressure during high-pressure, high-temperature (HPHT) diamond synthesis.


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