Effects of boron nitride and carbon nanotube on damping properties, thermal conductivity and compression stress relaxation behavior of BIIR

2021 ◽  
Author(s):  
Huanhuan Dong ◽  
Guojie Zhang ◽  
Yang Jiang ◽  
Yong Zhang
2018 ◽  
Vol 25 (5) ◽  
pp. 1015-1019 ◽  
Author(s):  
Muhammad Mansoor ◽  
Muhammad Shahid

AbstractThe mechanical properties and stress relaxation behavior of annealed aluminum-carbon nanotube composite were studied and compared with those of pure aluminum. The composite was prepared using an induction furnace, where 1.6 vol.% of multiwall carbon nanotubes were added in aluminum as strengthening material. It was found that the mechanical strength of the annealed composite was almost twice that of aluminum. The stress relaxation behavior of both materials was logarithmic in nature. However, the stress relaxation, hardening component, and intrinsic height of the thermally activated barrier were significantly influenced by the presence of nanotubes in the aluminum matrix. It was found that the stress relaxation rate of the composite was reduced (>30%) and the hardening component was increased (>100%) compared with that of aluminum. The calculated strengths of the thermally activated barriers for aluminum and the composite were 1.7 and 2.6 eV, respectively.


2016 ◽  
Vol 49 (5) ◽  
pp. 381-396 ◽  
Author(s):  
Farzad A Nobari Azar ◽  
Murat Şen

Natural rubber/chloroprene rubber (NR/CR) blends are among the commonly used rubber blends in industry and continuously are exposed to severe weather changes. To investigate the effects of accelerator type on the network structure and stress relaxation of unaged and aged NR/CE vulcanizates, tetramethyl thiuram disulfide, 2-mercaptobenzothiazole, and diphenyl guanidine accelerators have been chosen to represent fast, moderate, and slow accelerator groups, respectively. Three batches have been prepared with exactly the same components and mixing conditions differing only in accelerator type. Temperatures scanning stress relaxation and pulse nuclear magnetic resonance techniques have been used to reveal the structural changes of differently accelerated rubber blends before and after weathering. Nonoxidative thermal decomposition analyses have been carried out using a thermogravimetric analyzer. Results indicate that there is a strong interdependence between accelerator type and stress relaxation behavior, network structure, cross-linking density, and aging behavior of the blends. Accelerator type also affects decomposition energy of the blends.


2010 ◽  
Vol 107 (6) ◽  
pp. 063509 ◽  
Author(s):  
Xuanhe Zhao ◽  
Nathaniel Huebsch ◽  
David J. Mooney ◽  
Zhigang Suo

2013 ◽  
Vol 328 ◽  
pp. 950-954
Author(s):  
Wei Wei Zhang ◽  
Hong Xu ◽  
Hong Yuan Li

An analytical method based on a creep model is being developed to investigate the effect of retightening on stress relaxation behavior for high-temperature turbine and valve studs/bolts. In order to validate the approach, the calculated results are compared to the results of uniaxial reloading stress relaxation testing, which were performed by the National Research Institute for Metals of Japan (NRIM) for 12Cr-1Mo-1W-1/4V stainless steel bolting material at 550°C. It was shown that the proposed model based on Altenbach-Gorash-Naumenko creep model for the primary and steady state creep could be applied for the present data. The calculated residual stresses versus time curves were in good agreement with the measured for initial stress level of 273.6MPa at 550°C and for specific reloading time intervals of 24, 72, 240, and 720 hours.


2018 ◽  
Vol 6 (2) ◽  
pp. 025318 ◽  
Author(s):  
Muhammad Shafiq Irfan ◽  
Yasir Qayyum Gill ◽  
Motahira Hashmi ◽  
Sana Ullah ◽  
Farhan Saeed ◽  
...  

2016 ◽  
Vol 5 (4) ◽  
pp. 259-265 ◽  
Author(s):  
Ryutaro SHIODA ◽  
Yoshiharu KARIYA ◽  
Noritsuka MIZUMURA ◽  
Koji SASAKI

Sign in / Sign up

Export Citation Format

Share Document