scholarly journals Thin and temperature resistant TiO2-Sr1-xLaxTiO3 (x=0.1~0.3) composite ceramics for microwave absorption in the X-band

Author(s):  
Yingying Zhou ◽  
Qinlong Wen ◽  
Chaoqun Yang ◽  
Zhaowen Ren ◽  
Yuanyuan Lu ◽  
...  

Abstract Recently, high-temperature stability is a challenge in a number of microwave absorption materials. Hence, researchers are still searching for a novel material system preferably with a high-temperature resistance to be applied in the field of microwave absorption. Here, in the current study, toward this aim, lanthanum (La) doped strontium titanate (SrTiO 3 ) blended with TiO 2 were fabricated by hot-press sintering in vacuum. The as-prepared samples are denoted as TiO 2 -Sr 1- x La x TiO 3 with x varying from 0.1 to 0.3 in steps of 0.1. Scanning electron microscope (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscope (XPS), and microwave vector network analyzer were carried on to study their morphology, phase composition, structure, electromagnetic and microwave absorption properties, respectively. It is revealed that the La atom was efficiently doped at the Sr-site in SrTiO 3 . Benefiting from the tunability of its dielectric and impedance properties, TiO 2 -Sr 1- x La x TiO 3 can be utilized in a highly efficient way to absorb microwave radiations with a decent design. Results illustrated that TiO 2 -Sr 1- x La x TiO 3 ( x =0.2) with a thickness of only 0.42 mm exhibits a high microwave absorption efficiency of -40.89 dB and can achieve a 2.82 GHz bandwidth of reflection loss value below -5 dB. Thus, TiO 2 -Sr 1- x La x TiO 3 composites ceramics can be served as an opening opportunity for the application of high-temperature stability and tunable high-performance effectiveness microwave absorption materials in stealth technology and information security.

2015 ◽  
Vol 3 (2) ◽  
pp. 329-338 ◽  
Author(s):  
Fapeng Yu ◽  
Qingming Lu ◽  
Shujun Zhang ◽  
Hewei Wang ◽  
Xiufeng Cheng ◽  
...  

BiB3O6 crystals possess large piezoelectric coefficients and high-temperature stability of their piezoelectric properties, which is promising for piezoelectric sensor applications.


2011 ◽  
Vol 243-249 ◽  
pp. 4119-4124 ◽  
Author(s):  
Long Wen ◽  
Xiao Jiang Wang ◽  
Hao Liu ◽  
Hao Xiang Wu ◽  
Bao Lin Cui ◽  
...  

Buton rock asphalt (BRA) is possessed of both performance and economic advantages. In order to reveal the modification mechanism, X-ray diffraction experiment (XRD), X-ray fluorescence spectrum analysis and environmental scanning electron microscopy experiment (ESEM) are used to study on microstructure of BRA in this paper. It demonstrates that BRA can extremely adsorb free bitumen due to abundant microscopic pores, which consists of 70~80 percent Buton rock (BR) minerals and 20~30 percent pure rock asphalt (RA). RA with high viscosity is strongly adsorbed internal and outer of the surface of BR, which has high alkaline pH, high crystallization and strong surface activity. Then a special microstructure named “RA~BR” blend with stable property and strong spalling-resistance capability develops. Meanwhile, dynamic stability rheology test (DSR) is employed to study on the rheological mechanics property of BRA modified asphalt mastic. The high temperature performance grade (PG) level of BRA modified asphalt mastic with different mixing content is determined. The reasonable mixing content of BRA in matrix asphalt is 20~30 percent. The research proves that BRA modified asphalt possesses wonderful high temperature stability and has broad prospects for pavement application.


Coatings ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1029
Author(s):  
Cheng Gao ◽  
Yangsheng Jiang ◽  
Dayong Cai ◽  
Jinyong Xu ◽  
Jia Ding

Al2O3-MoSi2 coating has excellent high-temperature stability. On this basis, Al2O3-MoSi2-Cu composite high-temperature absorbing coating was prepared by atmospheric plasma spraying method. The phase transition characteristics of Al2O3-MoSi2-Cu spraying feedstock under high temperatures were analyzed by thermogravimetric test, the phase analysis of coating was performed by an in situ XRD test at different temperatures, and the microstructure of the coating was characterized by SEM. The test results of high-temperature microwave absorption performance show that, in high-temperature air atmosphere, the Cu in the coating is gradually transformed into Cu2O by oxygen atom diffusion, and the microwave absorption performance of the coating gradually increases with the increase in temperature. The 1.7 mm-thick coating at 500 °C has the best absorbing performance with a reflection loss (RL) value of −17.96 dB and an effective absorbing bandwidth (RL < −10 dB) in X-band of 2.42 GHz. The prepared Al2O3-MoSi2-Cu composite high-temperature absorbing coating takes into account the dual advantages of high-temperature stability and high-temperature absorbing properties.


1988 ◽  
pp. 351-357
Author(s):  
M. O. Eatough ◽  
T. L. Aselage ◽  
K. D. Keefer ◽  
D. S. Ginley ◽  
B. Morosin

2010 ◽  
Vol 93 (11) ◽  
pp. 3902-3907 ◽  
Author(s):  
James V.> Shanahan ◽  
Erich H. Kisi ◽  
Jennifer S. Forrester ◽  
Heather J. Goodshaw ◽  
Jennifer S. Zobec ◽  
...  

2021 ◽  
Vol 3 (3) ◽  
Author(s):  
Ayse Sezer Hicyilmaz ◽  
Ayse Celik Bedeloglu

AbstractPolyimides, high-performance polymers with superior properties such as high temperature stability, resistance to solvents and high strength, can be used in high-tech applications of the aerospace and aviation, medical or electronics industry in different forms (film, fiber, nanofiber, membrane, foam, adhesive or coating). Among these applications, coating has a special place and is used to develop advanced structures having high temperature resistance, flame retardancy and etc. for high tech industries via an economical and feasible way. Therefore, in this review, we aimed to report the broad application status of polyimide coatings by reviewing publications, patents and commercial products. Thus, this study can assist in selecting suitable polyimide types and production methods for polyimide coating applications and in understanding their applicability for future products.


2010 ◽  
Vol 645-648 ◽  
pp. 1231-1234 ◽  
Author(s):  
Hitoshi Umezawa ◽  
Kazuhiro Ikeda ◽  
Ramanujam Kumaresan ◽  
Shinichi Shikata

Because of the superior material properties of diamond, high performance in high-temperature power device application is demonstrated in both the computational and the experimental studies. A calculated Baliga limit of diamond Schottky barrier diode (SBD) based on 1D model indicates that an increase in on-resistance is highly expected within the high blocking voltage region and will be remarkable at high temperature conditions. Because of the high barrier height of diamond SBDs, the reverse leakage current is suppressed even at high temperatures. From the high-temperature stability test, stable interfaces of metal/diamond contact with constant Schottky barrier height have been confirmed. The SBD works for more than 1500 hrs at 400oC.


Sign in / Sign up

Export Citation Format

Share Document